09 Jan

11O and other invariant mass results at, beyond or isobarically anchored to the proton drip line

09 January 2019 - 4:10 PM
1200 FRIB Laboratory
Washington University in St. Louis

L.G. Sobotka

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The reconstruction of the continuum of light nuclei using the invariant mass technique has allowed us to: observe new isotopes, find many new excited states, improve level properties of known levels, find the only case of sequential 2p-2p decay, discover 2p decay between isobaric analog states, study the decay of the Hoyle state, find an unappreciated mechanism for the generation of extreme nuclear spin alignments, complete or reduce uncertainties of several isospin multiplets, and find new cases of near-threshold resonances. Our work impacts every isobar from A=5 to A = 18. This talk will have very brief discussions of how these experiments are done and a survey of some of the results mentioned above. The main foci of the talk will be recent results on 11O (the mirror of the iconic 11Li) and explaining near-threshold resonances in 9Li and 10Be. In both cases continuum cognizant shell models are exploited to shed light on the not-so-obvious entanglement of the continuum (or continua) on structure.
14 Jan

Reaction studies for heavy element nucleosynthesis

14 January 2019 - 12:30 PM
1400 Biomedical and Physical Sciences Building
University of Guelph

Dennis Muecher

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The synthesis of heavy elements via the r-process involves extremely neutron-rich nuclei. Compared to light nuclei, our understanding of the properties of heavy, neutron-rich nuclei is sparse. The next-generation radioactive ion beam facilities, like ARIEL (TRIUMF), FAIR (GSI) and FRIB will offer unique possibilities to probe such nuclei. I will give an overview about our current and future nuclear astrophysics program with reaccelerated beams at TRIUMF. The new TI-STAR silicon tracker detector, under development in an international collaboration at the University of Guelph and TRIUMF, is designed for experiments with heavy, exotic beams at the future ARIEL facility. TI-STAR coupled to the TIGRESS array of HPGe detectors and the new EMMA recoil separator will offer constraining neutron-capture rates in the A=130 key region of r-process nucleosynthesis. In certain r-process scenarios, nuclear fission and fission-recycling influences the abundance distribution of elements in a major way. I will present our experimental program to study fission properties of A=200 neutron-rich nuclei via quasi-free (p, 2p) scattering using the R3B experiment at FAIR.
16 Jan

An analysis of the 18g,m F (d,p)19F reactions in the rotational model and the Kerman Problem in the continuum*

16 January 2019 - 4:10 PM
1200 FRIB Laboratory
Lawrence Berkeley National Laboratory

Augusto Machiavelli

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In the first part of this seminar we will discuss the results of a recent HELIOS [1] measurement of the (d,p) reaction on 18F, from both the ground (1+ ) and isomeric (5+) states, to the members of the 19F ground-state band [2] in the rotational model. We consider the structure of 18,19F in terms of Nilsson single-particle orbits originating from the sd spherical levels coupled to a deformed core, and calculate the (d,p) spectroscopic strengths to 19F from both the ground and isomeric states following the framework reviewed in [3]. Our results show good agreement with the experiment and the shell model. In the second part, we will revisit Kermans Coriolis coupling paper [4] when one of the Nilsson states is a resonance in the continuum. Some preliminary results will be discussed. [1] A. Wuosmaa, et al. Nucl. Instrum. Methods, A580, 1290 (2007). [2] D. Santiago Gonzalez, et al. Phys. Rev. Lett. 120, 122503 (2018). [3] B. Elbek and P. O. Tjom, in Advances in Nuclear Physics, M. Baranger and E. Vogt eds. (Springer, Boston, MA, 1969). [4] A. Kerman, Mat. Fys. Medd. Dan. Vid. Selsk., no. 15 (1956). *This material is based upon work supported by the U.S. DOE, Office of Science, Office of Nuclear Physics, under Contract No. DEAC0205CH11231.
17 Jan

Neutron capture cross sections for weak r-process environments

17 January 2019 - 11:00 AM
1200 FRIB Laboratory
NSCL

Rebecca Lewis

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The majority of the heavy elements above Fe are produced in neutron capture processes. Understanding how the heavy elements are produced requires information about the astrophysical conditions of the process and the properties of a large number of exotic nuclei. The recent identification of a site for the rapid neutron capture process (r-process) in a neutron-star merger environment provides some information on the astrophysical conditions [1-3]. However, there is still a significant amount of nuclear inputs which require more information such as masses, -decay half-lives, and neutron-capture cross sections. There is also evidence that a separate process (the weak r-process) could be responsible for the production of the lighter r-process elements [4]. The short half-lives of the nuclei involved make direct cross section measurements very difficult, so indirect experimental techniques are important. The -Oslo method aims to reduce the uncertainty in two statistical properties of the compound nucleus that are used to calculate the neutron-capture cross section: the nuclear level density (NLD) and the -ray strength function (SF) [5]. An experiment at the National Superconducting Cyclotron Laboratory measured the -delayed  rays of nuclei in the A~70 region to extract NLD and SFs used to constrain neutron-capture cross sections of neutron-rich nuclei. The NLD and SF of 71Ni have been extracted from the  decay of 71Co using the -Oslo method and the neutron-capture cross section of 70Ni(n,)71Ni has been constrained. [1] B.P. Abbott et al. (LIGO Scientific Collaboration and Virgo Collaboration), PRL 119, 161101 (2017) [2] M.R. Drout, A.L. Piro, B.J. Shappee, C.D. Kilpatrick, J.D. Simon, C. Contreras, D.A. Coulter, R.J. Foley, M.R. Siebert, N. Morrell, et al., Science 358, 1570 (2017) [3] D. Kasen, B. Metzger, J. Barnes, E. Quataert, and E. Ramirez-Ruiz, Nature 551, 80 (2017) [4] C. Sneden, J.J. Cowan, and R. Gallino, Annu. Rev. Astron. Astrophys. 46, 241 (2008) [5] A. Spyrou, S.N. Liddick, A.C. Larsen, M. Guttormsen, K. Cooper, A.C. Dombos, D.J. Morrissey, F. Naqvi, G. Perdikakis, S.J. Quinn, et al., PRL 113, 232502 (2014)
17 Jan

B and B-delayed neutron decays of the N = 82 isotopes <sup>130</sup>Cd and <sup>131</sup>In measured with GRIFFIN

17 January 2019 - 2:00 PM
1200 FRIB Laboratory
University of Guelph

Ryan Dunlop

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Gamma-Ray Infrastructure For Fundamental Investigations of Nuclei (GRIFFIN) is a new high-efficiency γ-ray spectrometer designed for use in decay spectroscopy experiments with low-energy radioactive ion beams provided by TRIUMF's Isotope Separator and Accelerator (ISAC-I) facility. The high-efficiency GRIFFIN array is comprised of 16 Compton-suppressed large-volume HPGe clovers, and is designed to be used with a suite of ancillary detectors, providing a powerful and versatile tool for studying exotic nuclei.

The structures of N = 82 nuclei below doubly-magic 132Sn are crucial for calculations of the astrophysical r-process as these isotopes form “waiting-points” that play an important role in the formation and shape of the second r-process abundance peak. Many of the most neutron-rich N = 82 nuclei are, however, out of reach to the current generation of radioactive beam facilities and their properties must be calculated. In the past, shell-model calculations for the half-lives of these nuclei have been performed by adjusting the quenching of the Gamow-Teller (GT) operator in order to reproduce the half-life of 130Cd [1]. However, the calculated half-lives of the nuclei below 130Cd are known to be systematically too large. Recently, separate measurements with EURICA and GRIFFIN reported a shorter half-life for 130Cd leading to a re-scaling of the GT quenching by a constant factor for all nuclei in the region, resolving the discrepancy [2,3]. However, the reduced quenching of the GT operator creates a new discrepancy in the calculated half-life of 131In. The half-life measurements of nuclei in this region are complicated due to the presence of B-decaying isomers with comparable half-lives and large B-n branches, making γ-ray photo-peak gating with a high-resolution, high-efficiency γ-ray spectrometer, an ideal method to measure each of the isomeric half-lives. This talk will provide an overview of the GRIFFIN γ-ray spectrometer at TRIUMF-ISAC. The half-lives of 128-130Cd and 131In, as well as the spectroscopy of the one and two neutron-hole nuclei 131Sn and 130Sn will then be presented.

[1] M. Hannawald et al., Nucl. Phys. A 688, 578 (2001).
[2] R. Dunlop et al., Phys. Rev. C 93, 062801(R) (2016).
[3] G. Lorusso et al., Phys. Rev. Lett. 114, 192501 (2015).
18 Jan

Aspects of gamma-ray spectroscopy at TRIUMF-ISAC

18 January 2019 - 11:00 AM
1300 FRIB Laboratory

Aaron Chester

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Radioactive ion beams (RIBs) delivered by the Isotope Separator and Accelerator (ISAC) facilities at TRIUMF, Canada's particle accelerator centre, permit access to nuclear structure information for a wide range of radionuclides using gamma-ray spectroscopy techniques. The TIGRESS array of HPGe detectors, located in TRIUMF's ISAC-II facility, enables in-beam spectroscopy of re-accelerated beams. Electromagnetic transition rates measured using the recoil distance method (RDM) can be achieved using the TIGRESS Integrated Plunger (TIP). The commissioning and first RIB experiment using TIP, along with data analysis methods used to compare Geant4-simulated RDM lineshapes to experimental data will be presented. In many RIB experiments, an accurate measurement of the beam composition is desired. The TRIUMF Fast Ion Counter (TRIFIC), a gas counter device, has been constructed for this purpose. The successful commissioning of TRIFIC at TIGRESS will be discussed. Decay spectroscopy experiments can be performed at the GRIFFIN HPGe array located at TRIUMF's ISAC-I facility. Measuring the angular momentum of excited states, and the multipole order and mixing ratio of gamma-ray ray transitions via gamma-gamma angular correlations is an important part of the GRIFFIN program. Experimental effects complicate the determination of angular correlation coefficients measured directly from experimental data. Analysis methods for accurately determining these coefficients and their uncertainties using Geant4 simulations will also be presented.
22 Jan

Multi-Reference Energy Density Functional Calculations of Odd-Mass Nuclei

22 January 2019 - 11:00 AM
1200 FRIB Laboratory
UNC Chapel Hill

Benjamin Bally

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For more than forty years, the Energy Density Functional (EDF) method has proven to be a useful tool to study low-energy nuclear structure and reactions. In particular, its Multi-Reference (MR) formulation allows the study of complex phenomena that emerge in the strongly-correlated finite quantal system that is the atomic nucleus. The most advanced MR-EDF methods combine efficiently the idea of symmetry breaking and restoration with the mixing of different reference states by the Generator Coordinate Method (GCM) to include important static correlations, such as pairing or deformation, as well as beyond mean-field effects. To this day, it is the most advanced microscopic method at our disposal to tackle heavy-mass nuclei. In this seminar, I will talk about the recent developments achieved to describe odd-mass nuclei within the MR-EDF formalism as well as some of the challenges faced by the practitioners, in particular regarding the effective interactions currently used and the computational limits of such an approach. Indeed, the most advanced MR-EDF methods that combine symmetry restorations and/or configuration mixing are computationally demanding and require large-scale computing facilities. This has to be contrasted with the picturesque idea of EDF approaches as low-cost computing methods.
23 Jan

Advancing Penning trap mass spectrometry of rare isotopes at the LEBIT facility

23 January 2019 - 4:10 PM
1200 FRIB Laboratory
Michigan State University

Ryan Ringle

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The Low-Energy Beam and Ion Trap (LEBIT) facility [1] at the National Superconducting Cyclotron Laboratory (NSCL) remains the only facility that employs Penning trap mass spectrometry for high-precision mass measurements of rare isotopes produced via projectile fragmentation. This powerful combination of a fast, chemically insensitive rare isotope production method with a high-precision Penning trap mass spectrometer has yielded mass measurements of short-lived rare isotopes with precisions below 10 ppb across the chart of nuclides. The most recent LEBIT measurement campaigns have focused on fundamental interactions such as T=1/2 mirror decay Q-values (11C [2] and 21Na [3]), and superallowed [beta]-decay Q-values (14O [4]), the nuclear mass surface near N=40 (68,69Co [5]), and the rp-process (56Cu [6], 51Fe [7]). Most recently, for the first time LEBIT has been used for post-trap decay spectroscopy. In a proof-of-principle experiment isomerically purified beams of 70Cu were delivered to a decay station installed after the Penning trap. In order to expand the experimental reach of Penning trap mass spectrometry to nuclides delivered at very low rates, the new Single Ion Penning Trap (SIPT) has been built. SIPT uses narrowband FT-ICR detection under cryogenic conditions to perform mass measurements of high-impact candidates, delivered at rates as low as one ion per day, with only a single detected ion. Used in concert with the existing LEBIT 9.4-T mass spectrometer, the 7-T SIPT system will ensure that the LEBIT mass measurement program at NSCL will make optimal use of the wide range of rare isotope beams provided by the future FRIB facility. * This material is based upon work supported by the by the National Science Foundation under Contract No. PHY-1102511 and PHY-1126282. [1] R. J. Ringle, S. Schwarz, and G. Bollen, Int. J. Mass Spectrom. 349-350, 87 (2013). [2] K. Gulyuz, et. al, Phys. Rev. Lett. 116, 012501 (2016). [3] M. Eibach, et. al, Phys. Rev. C 92, 045502 (2015). [4] A. A. Valverde, et. al, Phys. Rev. Lett. 114, 232502 (2015). [5] C. Izzo, et. al, Phys. Rev. C 97, 014309 (2018). [6] A. A. Valverde, et. al, Phys. Rev. Lett. 120, 032701 (2018). [7] W.-J. Ong, et. al, Phys. Rev. C 98, 065803 (2018).
24 Jan

The Births and Deaths of Neutron Stars: Neutrinos, dense matter, and the r-process

24 January 2019 - 11:00 AM
1200 FRIB Laboratory
FRIB

Luke Roberts

26 Jan

Advanced Studies Gateway Event: Year of the Periodic Table: The synthesis of the elements in the stars and in the lab

26 January 2019 - 10:30 AM
1300 FRIB Laboratory
NSCL

Artemis Spyrou

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The elements we see around us are forged in the burning fires of stars. Nuclear energy and nuclear reactions are driving these fires, and the only way to understand how they work is by producing the relevant nuclei here on Earth and studying their properties. For this reason, among others, the most powerful rare isotope accelerator in the world, FRIB, is currently under construction in the heart of Michigan, on the campus of Michigan State University. Celebrating the International Year of the Periodic Table of Chemical Elements, this talk will focus on how each of the elements and their isotopes can be synthesized inside stars, and how FRIB will give us unique access to the rarest of these isotopes to help us better understand how the universe works.
28 Jan

JINA-CEE Science Cafe - Title to be announced

28 January 2019 - 1:00 PM
1400 Biomedical and Physical Sciences Building
30 Jan

Probing the fusion of neutron-rich nuclei with radioactive beams

30 January 2019 - 4:10 PM
1200 FRIB Laboratory
Indiana University

Sylvie Hudan

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Fusion in neutron-rich environments is presently a topic of considerable interest. For example, the optical emission spectrum from the neutron star merger GRB170817A clearly establishes this neutron-rich environment as an important nucleosynthetic site. A good approach to understand how fusion proceeds in neutron-rich nuclei is to measure the fusion excitation function for an isotopic chain of nuclei. An experimental program has been established to measure the fusion excitation function for light and mid-mass neutron-rich nuclei using low-intensity radioactive beams. The technique was initially demonstrated by measuring the fusion excitation functions for 18O and 19O nuclei incident on a 12C target. Using the ReA3 facility at NSCL, a 28Si target was bombarded with beams of 39,47K at near-barrier energies. Incident ions were identified on a particle-by-particle basis by [delta]E-TOF just upstream of the target. Fusion products were directly measured and identified by the E-TOF technique with high efficiency. The measured fusion excitation functions will be presented and compared with calculations.
01 Feb

Galactic chemical evolution model provides quantitative constraints on the r-process in dwarf galaxies

01 February 2019 - 2:00 PM
2025 FRIB Laboratory
California Institute of Technology

Gina Duggan

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It is a challenge to distinguish which of the proposed r-process candidate sites produce the observed r-process enrichment in galaxies. We tackle this question by using a galactic chemical evolution model to match the continual build-up of r-process elements seen in our recently published catalog of dwarf galaxy abundances. The simplicity of dwarf galaxies allows a simple galactic chemical evolution model to determine the sources of r-process material. We have the largest sample of the r-process element barium (almost 250 stars) in dwarf galaxies ever assembled. Our catalog of [Fe/H], [alpha/Fe] and [Ba/Fe] for several dwarf galaxies allows us to test the possible origins of the r-process to see if the proposed amounts and timescales of these contributions can match the observations. Specifically, we test if core-collapse supernovae (CCSNe, including rare magnetorotational core-collapse supernovae) or neutron star mergers (NSMs) are the dominant source of r-process. Our method is sensitive to the clearest observational difference of CCSNe and NSMs---how quickly these events occur after the stars are created. I will discuss the details of our one-zone galactic chemical evolution model and the preliminary results that suggest a large r-process contribution from NSMs is required to produce the barium trends observed in dwarf galaxies especially at early times.
05 Feb

Nuclear equation of state sensitivities in multi-messenger signals from core-collapse supernovae

05 February 2019 - 11:00 AM
1200 FRIB Laboratory
MSU

MacKenzie Warren

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We have explored the dependence of observable features from core-collapse supernovae (CCSNe) on the high-density nuclear equation of state. We have performed simulations of 138 supernovae progenitors ranging from 9-120 solar masses using several equations of state. Using multimessenger electromagnetic, gravitational wave, and neutrino emission from each simulation, we can determine correlations between observable quantities, the equation of state, and fundamental nuclear physics parameters.
06 Feb

Understanding the origin of the heavy elements using rare isotopes in the laboratory

06 February 2019 - 4:10 PM
1200 FRIB Laboratory
Michigan State University

Fernando Montes

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Nucleosynthetic processes responsible for the creation of heavy elements often involve unstable ions and reactions that are difficult to produce at the relevant energies in rare beam facilities. The recent observations of the Kilonova associated with GW170817 and observations of chemical abundances in metal-poor stars have shown that although neutron-star mergers have been confirmed as a heavy nuclei nucleosynthesis site, they may not be the only site (besides slow neutron capture or s-process sites) that may contribute to the chemical evolution of the Galaxy. This is particularly true for the elements up to silver, where there is evidence for contribution from multiple astrophysical sites to the chemical evolution of the Galaxy. Reliable nuclear physics is needed in order to disentangle these multiple contributions. In this talk I will review some of that evidence along with the important role that nuclear properties play in those processes. I will focus in the progress in our understanding of the rapid neutron capture process (r-process) and in new results on nucleosynthesis in core-collapse supernovae and neutrino-driven winds that produce elements up to silver. I will show some examples of recent nuclear physics measurements that address the need for better nuclear data and give an outlook of the remaining challenges and future plans to continue such measurements.
07 Feb

Current status of the Single Atom Microscope, a prototype detector for optically imaging the products of rare nuclear reactions

07 February 2019 - 11:00 AM
1200 FRIB Laboratory
Michigan State University

Ben Loseth

11 Feb

The BRIKEN project: extensive new beta- delayed neutron measurements for astrophysics

11 February 2019 - 12:30 PM
1400 Biomedical and Physical Sciences Building
University of Valencia

Jose Tain

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Beta delayed-neutron emission occurs for sufficiently neutron-rich nuclei when the decay populates states above the neutron separation energy in the daughter nucleus. It was discovered in fission- products soon after fission itself and it plays a key role in the control of nuclear reactors. The importance of this phenomenon in the description of rapid neutron capture (r-) processes occurring in explosive stellar scenarios with large neutron abundances was first pointed out in the seventies. The initial effect is the displacement to lower masses of the distribution of elements synthetized along the r-process path. In addition the delayed neutrons reactivate the neutron capture reactions with the opposite effect. The computation of the final isotopic abundances requires the knowledge of decay properties for very neutron-rich nuclei that have eluded until now direct experimental investigation. The BRIKEN project was launched to extend significantly our knowledge of beta-delayed neutron emission probabilities (Pn) and half-­‐lives (T 1/2) into this region, combining the very high beam intensity achieved at the RIBF accelerator complex in RIKEN and the selection/identification capabilities for reaction products of the BigRIPS in-flight spectrometer, together with state-of-the-art ion implant- and- decay detectors and moderated neutron counters. The experimental program started in 2017 and envisages the measurement of over 250 new beta-delayed neutron emitters, and 100 new half-lives covering the region from mass A~70 to A~200 with a direct impact in r-process nucleosynthesis calculations. Lighter mass (A=30-70) nuclei will also be investigated. The wealth of new data will allow a thorough benchmarking of nuclear structure dependent beta-strength calculations and the study of the competition between gamma-emission and different multi-neutron emission channels. In this presentation I will review the status of the experimental program and show some initial results.
13 Feb

Superallowed alpha decay to doubly magic 100Sn

13 February 2019 - 4:10 PM
1200 FRIB Laboratory
Argonne National Laboratory

Dariusz Seweryniak

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Alpha decay has been a probe of nuclear structure and clustering in nuclei since the dawn of nuclear physics. However, microscopic description of [alpha]-decay rates remains to be a challenge. The island of [alpha] emitters near the N=Z line, 'north-east' of 100Sn, provides valuable data on the role of proton-neutron correlations in the [alpha]-particle formation. In fact, superallowed [alpha] decay has been proposed to occur in this region due to enhanced interactions between neutrons and protons, which occupy the same orbitals. During the talk, the recent observation of the superallowed [alpha]-decay chain 108Xe-104Te to doubly magic 100Sn, using the recoil-decay correlation technique with the Argonne Fragment Mass Analyzer at ATLAS, will be presented. This is an important stepping-stone towards developing a microscopic model of [alpha] decay since it is only the second case of [alpha] decay to a doubly magic nucleus, besides the benchmark 212Po [alpha] decay to 208Pb. The decay properties of 108Xe and 104Te indicate that the reduced [alpha]-decay width in at least one of these nuclei is a factor of 5 larger than in 212Po, which confirms their superallowed character. More precise measurements of [alpha]-decay properties along the 108Xe-104Te chain and of the neighboring nuclei would be invaluable for quantitative comparisons with existing [alpha]-decay models.
14 Feb

Update on CHEX: A tool for exploring charge-exchange reaction theory

14 February 2019 - 11:00 AM
1200 FRIB Laboratory
NSCL

Terri Poxon-Pearson

19 Feb

Electric dipole moments in the era of the LHC

19 February 2019 - 11:00 AM
1200 FRIB Laboratory
UMass

Jordy de Vries

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The search for an understanding of fundamental particle physics that goes beyond the Standard Model (SM) has grown into a worldwide titanic effort. Low-energy precision experiments are complementary to collider searches and, in certain cases, can even probe higher energy scales directly. However, the interpretation of a potential signal, or lack thereof, is complicated because of the non-perturbative nature of low-energy QCD. I will use the search for electric dipole moments (EDMs), which aims to discover beyond-the-SM CP violation, as an example to illustrate these difficulties and how they can be overcome by combining (chiral) effective field theory and lattice QCD. I discuss how EDM experiments involving complex systems like nucleons, nuclei, atoms, and molecules constrain possible CP-violating interactions involving the Higgs boson, how these constraints match up to direct LHC searches, and the relevance of and strategies for the improvement of the hadronic and nuclear theory.
20 Feb

Probing High Temperature QCD via Jet Measurements in Heavy Ion Collisions: Results from ATLAS and Prospects for sPHENIX

20 February 2019 - 4:10 PM
1200 FRIB Laboratory
University of Illinois at Urbana-Champaign

Anne Sickles

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Collisions between two large nuclear at collider energies produce extremely high temperature QCD matter which is best described as consisting of deconfined quarks and gluons. A powerful tool to understand this matter is to use the high momentum quarks and gluons generated in hard scattering processes in the earliest stages of the nuclear collision as probes of the matter at later times. These measurements use modifications to the jet rates and properties induced by the scattering of the probes off the constituents of the matter to infer the nature of the interactions and constrain the properties of the matter. This talk will describe recent jet measurements in lead-lead collisions at 5.02 TeV collision energy using the ATLAS detector at the Large Hadron Collider. The prospects for making these measurements at lower collision energy, and thus lower temperature QCD matter, using the sPHENIX detector at the Relativistic Heavy Ion Collider will also be discussed. Together measurements at these two facilities provide a unique opportunity to understand high temperature QCD.
21 Feb

Charge radii of neutron-deficient calcium isotopes

21 February 2019 - 11:00 AM
1200 FRIB Laboratory
NSCL

Andrew Miller

23 Feb

The Transforming Power of the Periodic Table and How It Impacts Our Everyday Lives

23 February 2019 - 10:30 AM
1300 FRIB Laboratory
John A. Hannah Distinguished Professor of Chemistry

Angela Wilson

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The periodic table of elements provides the collection of puzzle pieces (elements) that form everything—from the food we eat to the cars we drive. As we have learned more about each of the puzzle pieces, the impact has been tremendous on the economy, on national security, and on our lives, from the development of new technologies to strategies towards improved health. This talk will provide a walk through the elements, with a significant focus on lesser known parts of the periodic table, demonstrating how the knowledge we have gained has been so impactful upon our everyday lives. Challenges and opportunities that drive our quest for further understanding of the elements will also be addressed.​
25 Feb

JINA-CEE Science Cafe
Topic: X-ray bursts and accreting neutron stars

25 February 2019 - 2:00 PM
1400 Biomedical and Physical Sciences Building
Michigan State University

Abbie Stevens Louis Wagner and

27 Feb

Radiological/nuclear emergency-response science at the Remote Sensing Laboratory

27 February 2019 - 4:10 PM
1200 FRIB Laboratory
Remote Sensing Laboratory

Scott Suchyta

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The mission of the DOE/NNSA Office of Emergency Response is to provide a versatile, capable, worldwide nuclear or radiological response with the technical capability to respond to any radiological/nuclear incident worldwide. Scientists at the Remote Sensing Laboratory (RSL) play an important role in this mission, serving on a variety of response teams. An overview of various radiological emergency-response assets will be given, with a primary focus on the expertise of RSL. Current capabilities and operational challenges in the topic areas of both crisis response (radiological search, identification, characterization, etc.) and consequence management (response to and mitigation of incidents) will be discussed. A wide range of radiation-detection platforms, including backpacks, vehicle-mounted systems, and aircraft-mounted systems will also be presented.
28 Feb

HiP- Highlights in Progress

28 February 2019 - 11:00 AM
1200 FRIB Laboratory
NSCL

Robert Elder and Mark-Christoph Spieker

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Robert Elder, NSCL- Reaction and Lifetime Studies of 32Mg through 2-proton knockout Mark-Christoph Spieker, NSCL- One-proton and one-neutron knockout reactions from N = Z =28 56Ni to the A = 55 mirror pair 55Co and 55Ni
01 Mar

JINA-CEE Online Seminar - R-process nucleosynthesis in neutron star mergers and collapsars

01 March 2019 - 2:00 PM
2025 FRIB Laboratory
Columbia University

Dan Siegel

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Combining the kilonova observations of the neutron-star merger GW170817 and general-relativistic magnetohydrodynamic simulations, I will argue that the rapid neutron-capture (r-process) elements synthesized in GW170817 originate from powerful outflows of a post-merger accretion disk. Similar accretion flows are expected following the collapse of rapidly rotating massive stars ('collapsars') that are thought to power long gamma-ray bursts. Based on recent progress in our understanding of the evolution of both neutron-star mergers and collapsars, I will confront first-principle theoretical predictions with observations of r-process enrichment, and argue that collapsars are likely the dominant source of heavy r-process elements in the Milky Way. In particular, enrichment through collapsars appears to solve a number of problems related to r-process abundances in stars of the Milky Way disk and the halo, as well as in dwarf galaxies and globular clusters. I will also discuss how future multimessenger observations can help to directly probe or constrain r-process nucleosynthesis in collapsars.
06 Mar

Simulating nuclei from scratch

06 March 2019 - 12:00 PM
1200 FRIB Laboratory
FRIB

Dean Lee

11 Mar

JINA-CEE Lunchtime Seminar - A link between atomic physics and gravitational wave spectroscopy

11 March 2019 - 12:30 PM
1400 Biomedical and Physical Sciences Building
Los Alamos National Laboratory

Christopher Fontes

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Neutron star mergers are promising candidates for the observation of an electromagnetic (EM) signal coincident with gravitational waves. The recent observation of GW170817 [1] appears to be such an event, with gravitational waves confirmed by subsequent EM signals ranging from the infrared to x-ray portions of the spectrum. The properties of the ejecta produced during these events are predicted to play an important role in the electromagnetic transients called macronovae or kilonovae. Characteristics of the ejecta include large velocity gradients and the presence of heavy r-process elements, which pose significant challenges to the accurate calculation of radiative opacities and radiation transport. For example, these opacities include a dense forest of bound-bound features arising from near-neutral lanthanide and actinide elements. We use the Los Alamos suite of atomic physics and plasma modeling codes [2] to investigate the use of detailed, fine-structure opacities [3] to model the EM emission from macronovae. Our simulations [4] predict emission in a range of EM bands, depending on issues such as the presence of winds, elemental composition, and viewing angle. This talk emphasizes various atomic-physics aspects of the spectral modeling of neutron star mergers.
12 Mar

Tentative Thesis Title: “Eigenvector Continuation of Anharmonic Oscillator”

12 March 2019 - 9:00 AM
1221A FRIB Laboratory
NSCL Graduate Student

Avik Sarkar

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COMMITTEE: Dean Lee (Chairperson), W. Lynch T. Parker, J. Schenker, V. Zelevinksy
13 Mar

Constraining the equation of state of asymmetric nuclear matter at high densities with heavy ion collisions

13 March 2019 - 4:10 PM
1200 FRIB Laboratory
GSI Helmholtzzentrum fuer Schwerionenforschung

Yvonne Leifels

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Heavy-ion collisions provide the only means to explore densities different from the saturation density as in the course of such a collision matter suffers compression and expansion phases. In the energy range accessible to the SIS accelerator (0.1-1.5 GeV/u) at GSI nuclear matter is compressed up to thrice normal nuclear matter density. A multitude of observables have been studied --- as a follow-up of the pioneering work done at the heavy ion accelerator at Berkeley in the eighties and early nineties --- by various experiment at GSI and a rather complete observable data base spanning large energy ranges in sufficiently small steps has been collected and has been confronted with the prediction of microscopic transport models to constrain nuclear matter properties. The symmetry energy is the part of the nuclear matter connected to the neutron/proton asymmetry. During recent years a multitude of experimental and theoretical efforts in the fields of nuclear structure, heavy ion reactions and astrophysics have been undertaken to constrain its density dependence. Apart from data on astrophysical objects like neutron star masses and radii, and neutron star merger events, heavy ion reactions at several 100 MeV/u are the only means to access the high density dependence. In particular, meson production and the and collective flows up to 1 GeV/u are predicted to be sensitive to the density dependence of the symmetry energy. Ratios and differences of neutron to hydrogen flows were measured in Au+Au collisions at 400 MeV/u at GSI. The comparison with predictions of transport models favors a moderately soft to linear density dependence slightly above normal nuclear matter densities, which is consistent with ab-initio nuclear matter theories. Further, the models predict that with comprehensive data sets collected at higher incident energies the equation of state of asymmetric nuclear matter could be constrained up to two to three times normal nuclear matter density.
14 Mar

Nuclear astrophysics with active-target time projection chamber

14 March 2019 - 11:00 AM
1200 FRIB Laboratory
Michigan State University

Jaspreet Randhawa

18 Mar

Another FRIB impact: Is tomography of heavy ions experimentally possible?

18 March 2019 - 11:00 AM
1200 FRIB Laboratory
Michigan State University

Paul Gueye

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The electromagnetic probe is one of the cleanest tools to probe the nuclear matter due to its point-like nature. It has enabled some key understandings of the nuclei charge distributions, spin-dependent observables and opened a path to 3D nucleons femtography. Nuclei structures are best studied with heavy ion facilities that have unraveled and provided fundamental insights of new isotopes, with the shell model at its core for spectroscopy guidance. While many advances and discoveries have occurred, they also brought new challenges in this fascinating world of nuclear physics: we are still trying to understand how big the proton is, how far can we go on both the proton and neutron driplines, are neutron stars actually strange stars and how nucleon pairs interact inside nuclei to name a few. This talk will highlight some shortcomings of the Born approximation in electron scattering along with their relations to heavy ion studies with facilities like FRIB and the possibility to enable a 3D tomography of the nuclear matter. Another key factor in the advancement of nuclear physics is rooted in its diverse pool of scientists and engineers, an aspect that will also be highlighted.
19 Mar

Recent advances in ab initio nuclear theory: From symmetry breaking to pre-processing tools

19 March 2019 - 11:00 AM
1200 FRIB Laboratory
CEA Saclay

Alexander Tichai

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In recent years the ab initio treatment of the nuclear many-body problem has seen tremendous progress such that the A-body Schroedinger equation can be solved from first principles using realistic nuclear Hamiltonians with a sound link to QCD. However, it is yet unclear (1) how to describe genuine open-shell nuclei from an ab initio perspective and (2) how to overcome the curse of dimensionality in many-body approaches that prevents relaxing many-body approximations. Additionally, the large uncertainties arising from the input Hamiltonian make a direct comparison with experimental observations challenging, requiring extensive interaction benchmarks far away from shell closures and for large mass numbers in the future. Exploiting symmetry breaking in the many-body expansion enables for addressing nuclear observables in arbitrary open-shell systems. The recently introduced Bogoliubov extension of many-body perturbation theory serves as an example for a computationally light-weighted approach well-suited for benchmarking ground-state energetics along medium-mass isotopic chains. In a complementary way, data pre-processing techniques help resolving the computational bottlenecks one is facing in state-of-the-art many-body implementations. Two particular strategies are discussed: (i) tensor factorization and (ii) importance truncation. Following rationale (i), many-body tensors, like the Hamiltonian, are decomposed into lower-rank objects and consequently, storage requirements are decreased and, at the same time, the contraction pattern of the tensor network is optimized. Importance truncation, on the other hand, aims at an a priori selection of Hilbert space basis states which are expected to be important based on a (typically perturbative) importance measure. Due to discarding many irrelevant tensor entries the original large-scale problem can be solved in a much smaller selected model space. The combination of novel many-body expansions and innovative tools from applied mathematics allow for extending the range of ab initio applications and, thus, putting the next generation of nuclear Hamiltonians to a stringent test at a low computational cost.
20 Mar

Precision measurements of mirror transitions at the Nuclear Science Laboratory

20 March 2019 - 4:10 PM
1200 FRIB Laboratory
University of Notre Dame

Maxime Brodeur

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Despite its success, the Standard Model (SM) is currently being scrutinized at the energy, intensity and precision frontier. One probing mechanism for new physics is the unitarity test of the Cabibbo-Kobayashi-Maskawa matrix. This test requires a precise and accurate determination of the Vud matrix element, which is currently derived from the ft-value of superallowed weak decays. While superallowed pure Fermi transitions currently allow for the most precise determination of Vud, there is currently a growing interest in obtaining that matrix element from superallowed mixed transitions to test the accuracy of Vud and the calculation of isospin symmetry breaking corrections. In the past few years a research program aimed at solidifying the determination of Vud from mirror transitions was initiated using radioactive ion beams from the Twin Solenoid (TwinSol) separator at the Nuclear Science Laboratory of the University Notre Dame. The first part of the program is centered on precision half-life measurements and the second part aims at measuring the Fermi to Gamow-Teller mixing ratio ρ. Recent half-life measurements and the current development status of an ion trapping system to measure ρ in many mirror decays for the first time will be presented.
21 Mar

Renormalization of CP-violating operators in perturbative QCD using the Yang-Mills gradient flow

21 March 2019 - 11:00 AM
1200 FRIB Laboratory
Michigan State University

Matthew Rizik

22 Mar

Advanced Studies Gateway Event: Musical Connection Beyond the Border

22 March 2019 - 5:30 PM
1300 FRIB Laboratory

Igor Cetkovic, Wei-Qin Claire Tang

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A Chamber Music Recital Featuring Igor Cetkovic (cello) and Wei-Qin Claire Tang (piano)
25 Mar

JINA-CEE Science Cafe - "Discovering New Classes of Millisecond Pulsar Binaries" and "Spallation in the atmospheres of accreting neutron stars and impact on X-ray bursts"

25 March 2019 - 1:00 PM
1400 Biomedical and Physical Sciences Building
Michigan State University

Sam Swihart and Jaspreet Randhawa

27 Mar

Imaging Individual Barium Atoms in Solid Xenon for the nEXO Neutrinoless Double Beta Decay Experiment

27 March 2019 - 4:10 PM
1200 FRIB Laboratory
Colorado State University

William Fairbank

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Neutrinoless double beta decay is a rare and yet unobserved process that violates conservation of lepton number. Observation of neutrinoless double beta decay would represent the discovery of new physics beyond the Standard Model of elementary particles. This would include confirmation of the Majorana character for neutrinos, i.e., that the neutrino is its own antiparticle. It also could contribute to an understanding of the mystery of the missing anti-matter in our universe from the Big Bang. The proposed nEXO experiment utilizes the isotope 136Xe in a liquid xenon time-projection chamber and aims to achieve a half-life sensitivity of about 1x1028 years. As a potential add-on to this experiment, we are developing a technique to identify or "tag" the 136Ba daughter atom that results from double beta decay of one 136Xe atom. This extra decay signature could be used to eliminate all false radioactive backgrounds in nEXO that do not produce a 136Ba daughter. This would enhance the sensitivity of nEXO, and the extra confirmation would be valuable if a positive signal is found. The proposed Ba tagging scheme utilizes a cryogenic probe to trap the barium daughter atom in solid xenon and extract it from the time projection chamber. The observation of a single barium atom in the laser scan of the solid xenon matrix on the widow at the end of the probe would be a positive confirmation of a true double beta decay event. Individual barium atoms in solid xenon have been detected and imaged with high signal-to background fluctuation ratio by scanning a focused laser across the solid xenon matrix deposited on a cold sapphire window. By fixing the laser position on a single Ba atom, it is found that the fluorescence suddenly drops to background level. This is a clear signature of a single atom. A remarkable result is that heating the matrix to 100 K “erases” all signal from a previous Ba deposit. To our knowledge, this is the first time that single atoms have been imaged in solid noble gas and represents significant progress towards a practical barium tagging technique for the proposed nEXO neutrinoless double beta decay experiment.
28 Mar

APS April Meeting Practice Talks

28 March 2019 - 11:00 AM
1200 FRIB Laboratory
Michigan State University

Xingze Mao, Jason Surbrook, Daniel Rhodes, and Ben Loseth

30 Mar

Is There an End to the Periodic Table of Elements?

30 March 2019 - 10:30 AM
1300 FRIB Laboratory
Hannah Distinguished Professor

Witek Nazarewicz

02 Apr

Quantum computing for nuclear physics

02 April 2019 - 11:00 AM
1200 FRIB Laboratory
University of Washington

Alessandro Roggero

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Quantum Computers have the potential to dramatically extend the reach of our theoretical modelling of complex quantum many body systems. In this talk I will explore the impact that this technology can have on the study of structure and reactions of atomic nuclei. As an example, an ab-initio description of nuclear dynamics is currently out of reach for most systems of interest, however with only a mid-sized quantum computer efficient calculations of both inclusive and exclusive nuclear cross sections would be possible. In the talk I will explore an application of this strategy to describe reactions of relevance for long base-line neutrino experiments. Current generations quantum devices are however too small and too noisy to already tackle realistic problems in nuclear physics, in the last part of the talk I will discuss some of the challenges one has to face when implementing practical quantum algorithms to study the properties of the simplest nuclear many-body system: the deuteron.
03 Apr

Cluster structure and three-body decay in 14C

03 April 2019 - 9:30 AM
1200 FRIB Laboratory
NSCL Graduate Assistant

Lisa Carpenter

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Committee: Wolfgang Mittig(Chairperson), Daniel Bazin, Carl Bromberg, Scott Pratt, Vladimir Zelevinsky Thesis is on display in 1312 BPS bldg. and the NSCL atrium
03 Apr

Delivering a nuclear science capability at Lawrence Livermore National Laboratory

03 April 2019 - 4:10 PM
1200 FRIB Laboratory
Lawrence Livermore National Laboratory

Teresa S. Bailey

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Predictive science is one of Lawrence Livermore National Laboratory's (LLNL) most important mission areas, as well as one of our strengths. We use predictive science to improve fundamental understanding of our applications, through the integration of focused experiments, theory research and development, numerical methods research, and high-fidelity simulations. The LLNL Nuclear Science efforts provide important nuclear data to help drive improvements in our predictive capability. As a result, we have developed and continually maintain a complete nuclear data pipeline, which integrates nuclear physics experiments and theory to produce new data libraries. These new data libraries are processed for use within particle transport codes. Important physics is added at each step in this process. In this presentation, we will walk through the pipeline, providing an overview of LLNL's capability in each area, and a focus on delivering data for the end-user. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.
04 Apr

HiP - Highlights in progress: Nucleon electric dipole moment results from lattice QCD using the gradient flow

04 April 2019 - 11:00 AM
1200 FRIB Laboratory
Michigan State University

Andrea Shindler

04 Apr

NuSTAR/X-ray searches for sterile neutrino dark matter

04 April 2019 - 3:30 PM
1415 Biomedical and Physical Sciences Building
Massachusetts Institute of Technology

Kerstin M. Perez

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Cosmic-ray antiprotons have been a valuable tool for dark matter searches since the 1970s. Recent years have seen increased theoretical and experimental effort towards the first ever detection of cosmic-ray antideuterons, in particular as an indirect signature of dark matter annihilation or decay in the Galactic halo. In contrast to other indirect detection signatures, which have been hampered by the large and uncertain background rates from conventional astrophysical processes, low-energy antideuterons provide an essentially background-free signature of dark matter, and low-energy antiprotons are a vital partner for this analysis. I will discuss the upcoming balloon-borne GAPS experiment, which exploits a novel detection technique utilizing exotic atom capture and decay to provide sensitivity to antiproton, antideuteron, and antihelium cosmic-ray signatures. In particular, I will detail the fabrication of the lithium-drifted Silicon detectors that are essential to its success.
10 Apr

Determining the properties of the quark-gluon plasma from experiment

10 April 2019 - 4:10 PM
1200 FRIB Laboratory
Michigan State University

Scott Pratt

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For the past 2 decades, experiments at the Relativistic Heavy Ion Collider and at the LHC have measured heavy-ion collisions at high energies, with the purpose of creating and measuring transient drops of the quark gluon plasma (QGP). Validating the creation of the QGP and extracting fundamental bulk properties involves detailed modeling, creative phenomenology and advanced statistical analysis. I will review the status of the field in determining the equation of state, chemistry, viscosity and diffusivity of the QGP as determined from such analyses.
11 Apr

Towards a more sensitive measurement of the permanent electric dipole moment of Radium-225

11 April 2019 - 11:00 AM
1300 FRIB Laboratory
Michigan State University

Roy Ready

15 Apr

JINA-CEE Seminar - Gamma-ray spectroscopy from nuclei in the cosmos

15 April 2019 - 12:30 PM
1400 Biomedical and Physical Sciences Building
MPE Garching

Roland Diehl

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Gamma-ray spectroscopy from nuclei in the cosmos Roland Diehl, Max Planck Institut für extraterrestrische Physik Gamma ray lines from cosmic sources display the action of nuclear reactions in cosmic sites. The gamma rays at such characteristic energies result from nuclear transitions following radioactive decays or high-energy collisions with excitation of nuclei. The gamma-ray line and its associated special continuum from the annihilation of positrons at 511~keV falls into the same energy window, although of different origin. We review the concepts of astronomical gamma-ray telescopes and cosmic gamma ray spectrometry, with the corresponding instruments and missions, including future perspectives. We then present a discussion of recent results and the challenges and open issues for the future. This includes, specifically, the diffuse radioactive afterglow of massive-star nucleosynthesis in $^{26}$Al and $^{60}$Fe gamma rays, which is now being exploited towards the cycle of matter driven by massive stars and their supernovae. Also the complex processes making stars explode as either thermonuclear or core-collapse supernovae are subject to studies through gamma-ray lines, in this case from shortlived radioactivities from $^{56}$Ni and $^{44}$Ti decays. Herein the non-sphericities that have recently been recognised as important are reflected, probably most-directly, through gamma-ray line characteristics. We will also discuss how we should relate to the above the distribution of positron annihilation gamma ray emission with its puzzling bulge-dominated intensity distribution, which is measured through spatially-resolved spectra. These indicate that annihilation conditions may differ in different parts of our Galaxy, and helps to reveal the complex paths recycling matter from nucleosynthesis sources to next-generation stars.
16 Apr

Utilizing correlations in fission observables

16 April 2019 - 11:00 AM
1200 FRIB Laboratory
LANL

Amy Lovell

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Accurately describing the fission process from the formation of a compound nucleus to the emission of prompt and delayed particles is important for fundamental science calculations as well as for a variety of applications such as stockpile stewardship and non-proliferation. Monte Carlo codes, which calculate fission on an event-by-event basis, are useful to study correlations between fission observables. The LANL-developed Monte Carlo code CGMF samples the initial conditions of the two daughter fragments which then emit neutrons and gamma rays in a Hauser-Feshbach decay. Due to energy conservation, the numbers of neutrons and gamma rays that are emitted along with their energies are all strongly corrected, allowing us to extract information about the emitted neutrons from measurements of the gamma rays - and vice versa. Motivated by recent measurements of prompt gamma rays from 252Cf spontaneous fission at LANL, we extract the neutron multiplicity distribution from correlations between gamma ray energies and fragment kinetic energies. We also compare this direct method to a machine learning algorithm that learns these correlations and discuss future directions for this work.
17 Apr

Electric dipole response of nuclei and damping of IVGDR

17 April 2019 - 4:10 PM
1200 FRIB Laboratory
Research Center for Nuclear Physics, Osaka University

Atsushi Tamii

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Electric dipole (E1) excitation is one of the fundamental excitation modes in atomic nuclei. The IsoVector Giant Dipole Resonance (IVGDR) is a well-known collective excitation that is macroscopically described as a dipole oscillation between protons and neutrons. An additional concentration of the E1 strength has been found in the vicinity of the neutron separation energy of neutron rich nuclei, that is discussed under the concept of Pygmy Dipole Resonance (PDR). By taking the inversely energy-weighted sum rule of the E1 transition probability, the static E1 polarizability can be extracted. The polarizability in medium and heavy nuclei, like 120Sn or 208Pb, is predicted by mean-field model calculations to be well-correlated with the symmetry energy parameters of the nuclear equation of state as well as the neutron skin thickness. We have been investigating the E1 response of stable nuclei by using proton scattering at very forward angles and at 295 MeV [1] by using high-resolution magnetic spectrometer Grand Raiden at the Cyclotron Facility of the Research Center for Nuclear Physics (RCNP), Osaka University. Quite a few physics results were obtained from a series of experimental works in the last decade [2]. In this seminar, I firstly briefly pick up the results on the electric dipole polarizabilities together with the relevant experimental technique. Then, I will show a recent extension of the experimental work to a gamma-decay coincidence measurement [3] by using large-volume LaBr3:Ce detectors in collaboration with a Milano group. It is a pilot experiment aiming at studying the width and the damping mechanism of the IVGDR by measuring the gamma decay to the ground state. The first target nucleus was 90Zr. We successfully measured the gamma decays with a branching ratio of [approximately] 1% in coincidence with the excitation by proton scattering. I plan to show preliminary results and physical interpretations. [1] A. Tamii, et al., Nucl. Instrum. and Meth. in Phys. Res. A 605, 326 (2009). [2] P. von Neumann-Cosel and A. Tamii, submitted to Euro. Phys. J. A. [3] RCNP-E498: S. Nakamura, A. Bracco, P. von Neumann-Cosel, A. Tamii, et al.
18 Apr

Beta-delayed charged particle measurements for studies of novae and X-ray bursts

18 April 2019 - 11:00 AM
1200 FRIB Laboratory
Michigan State University

Moshe Friedman

19 Apr

Ab Initio Simulations of Light Nuclear Systems Using Eigenvector Continuation and Auxiliary Field Monte Carlo

19 April 2019 - 11:00 AM
1200 FRIB Laboratory
NSCL Graduate Research Assistant

Dillon Frame

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Committee: Dean Lee(Chairperson), Soctt Bogner, Kei Minamisono, Luke Roberts, Jeffrey Schenker, Andrea Shindler
22 Apr

JINA-CEE Science Cafe - Discussing "Observations of classical novae across the electromagnetic spectrum" and "Experimentally constraining reaction rates to understand nova nucleosynthesis", respectively

22 April 2019 - 1:00 PM
1400 Biomedical and Physical Sciences Building

Kirill Sokolovsky and Tamas Budner, Michigan State University

24 Apr

Ab initio studies of correlations effects in exotic isotopes

24 April 2019 - 4:10 PM
1200 FRIB Laboratory
University of Surrey

Carlo Barbieri

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Post Hatree-Fock methods of many-body theory are now capable to provide ab initio predictions of nuclei up to masses of A [approximately] 100 nucleons. Among these, I will concentrate on the self-consistent Green's function approach (SCGF) that allows direct access to the nuclear spectral functions and the information on nuclear correlations contained in it. The SCGF was the first of such methods to be extended to open shell isotopes and has been used extensively to benchmark chiral nuclear interactions and to investigate the single-particle structure of neutron rich nuclei. In this talk I plan to discuss (1) our results regarding the dependence of shell closures and spectroscopic factors on isospin asymmetry, (2) the application of SCGF to develop microscopic optical potentials and (3) the importance of knowing the spectral functions for understanding the response to neutrinos under the wide range of energies relevant to oscillation experiments.
26 Apr

Astrophysical Applications of Gamow-Teller Strengths in the A=78-100 Region

26 April 2019 - 10:30 AM
1200 FRIB Laboratory
NSCL Graduate Assistant

Rachel Charlotte Taverner Titus

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Committee: Remco Zegers(Chairperson), B. Alex Brown, Sean Couch, Morten Hjorth-Jensen, Artemis Spyrou (Thesis is on display in 1312 BPS bldg. and the NSCL Atrium)
26 Apr

Advanced Studies Gateway Event: Orpheus and Euridice: Myth Meets #MeToo

26 April 2019 - 5:30 PM
1300 FRIB Laboratory

Ann Montgomery, Sam Davies, Ling Lo, Peter Boylan

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In this semi-staged production of Ricky Ian Gordon’s Orpheus and Euridice, enter into a modern reimagining of Virgil’s classic myth of love, loss, and beauty by setting it within the context of today’s #MeToo movement. What if it wasn’t a snake that attacked Euridice? What if she didn’t die and descend to Hades, but instead the world as she knew it crumbled around her after a sexual assault, becoming her own personal living hell? What can Orpheus do to try to rescue her from a situation she can’t find words to express? How can goodness and beauty come out of all this suffering? There is a powerful message of hope and strength in this piece. Join us for our musical journey.
27 Apr

Amazing things about the periodic table you never learned from chemistry

27 April 2019 - 10:30 AM
1300 FRIB Laboratory
NSCL Director

Brad Sherrill

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As 2019 is the year of the period table, it is fun to consider some of the lesser-known aspects of this powerful and useful way to organize the building blocks of our world. This talk will review some of the history of elements and the efforts to develop an understanding of nature. It will also explore the existence of isotopes (roughly translated from Greek as “at the same place”) of the elements. We think of elements as unchanging, but this is not correct. Radioactivity is evidence for one element changing into another and is a part of nature. A somewhat related topic was the goal of alchemists to transform metals to gold, the element that was considered perfect, and to find a path to perfection. They had no idea of radioactivity, or of what it would really take to change one element into another. We will look at the transformation of elements from a modern perspective and talk about how at least part of the goal of alchemy has been achieved by research laboratories such as FRIB.
29 Apr

Nuclear Reactions Away from Stability: From Exploding Stars to Exotic Structures

29 April 2019 - 2:00 PM
1300 FRIB Laboratory
Texas A&M University

Gregory Christian

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In the past 20 years, advances in accelerator and detector technologies have ushered in a new era of experimental nuclear physics. In particular, the advent of accelerated beams of rare isotopes, combined with sophisticated detector systems and novel measurement techniques, has allowed for detailed studies of the structure and reactions of nuclei far from stability. These experiments target fundamental questions such as the origin of the elements, the limits of nuclear binding, and the emergence of complex phenomena in nuclei. Furthermore, they provide crucial proving grounds for ab initio theories, which attempt to describe nuclear structure from first principles. Looking forward, next-generation rare isotope facilities such as FRIB will soon usher in a new generation of experiments on nuclei away from stability. In this talk, I will present an overview of past, present, and future experiments focused in two distinct, yet related areas: understanding nucleosynthesis and energy generation in stellar explosions, and understanding the structure of light nuclei far from stability. In particular, I will discuss recent and planned experiments at the TRIUMF-ISAC and Texas A&M Cyclotron Institute accelerator facilities. These experiments investigate nucleosynthesis in classical novae and the s-Process, as well as the structure of light, neutron-rich nuclei. Finally, in the closing minutes of the talk I will present some new ideas for performing simultaneous reaction measurements on a wide range of nuclei far from stability - a technique that holds promise to significantly expand the range of science that can be studied at FRIB.
30 Apr

New searches for rare Kaon decays

30 April 2019 - 1:30 PM
1400 Biomedical and Physical Sciences Building
University of Michigan

Brian Beckford

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The KOTO experiment was designed to observe and study the K_L→πνν ̅ decay. The Standard Model (SM) prediction for the mode is 2.4 x 〖10〗^(-11) with a small theoretical uncertainty [1]. An experimental upper limit of 2.6 x 〖10〗^(-8) was set by the KEK E391a collaboration [2]. The rare “golden” decay is ideal for probing for physics beyond the standard model. A comparison of experimentally obtained results with SM calculations permits a test of the quark flavor region and provides a means to search for new physics. The signature of the decay is a pair of photons from the π0 decay and no other detected particles. For the measurement of the energies and positions of the photons, KOTO uses a Cesium Iodide (CSI) electromagnetic calorimeter as the main detector, and hermetic veto counters to guarantee that there are no other detected particles. KOTO’s initial data was collected in 2013 and achieved a similar sensitivity as E391a result [3]. Since then, we completed significant hardware upgrades and had additional physics runs in 2015 at beam powers of roughly 24-40 kW. This presentation will present new results from KOTO and its present status on the search for detecting〖 K〗_L→πνν ̅. [1] C. Bobeth, A. J. Buras, A. Celis, and M. Jung, J. High Energy Phys. 04, 079 (2017). [2] J. K. Ahn et al., Phys. Rev. D 81, 072004 (2010). [3] J. K. Ahn et al., Prog. Theor. Phys. 021C01 (2017).
01 May

Constraining the Nuclear Symmetry Potential from Neutron and Proton Observables

01 May 2019 - 1:30 PM
1200 FRIB Laboratory
NSCL Graduate Student

Chi-En Teh

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Committee: Betty Tsang(Chairperson), E. Brown, L. Chomiuk, P. Danielewicz, W. Lynch
01 May

Collisions near the barrier: intertwining nuclear structure and reaction dynamics

01 May 2019 - 3:30 PM
1300 FRIB Laboratory
Tokyo Institute of Technology

Kaitlin Cook

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Nuclear reactions occurring at energies near the fusion barrier are uniquely sensitive probes of the interplay between nuclear structure and dynamics. Understanding these effects provides key insights into the nuclear many-body problem, as well as providing input into other problems, such as attempts to synthesize new superheavy elements. As more exotic weakly bound isotopes become accessible at new accelerator facilities, it is becoming critically important to understand the influence of weak binding on reaction dynamics, including on fusion. A persistent unsolved problem in near-barrier reaction dynamics is the observed ~30% suppression of complete fusion in above-barrier reactions of light weakly-bound nuclei (e.g., 6,7,8Li, 9Be). Previously thought to be a result of breakup prior to reaching the fusion barrier, my work has shown that the yields and characteristic timescales of breakup cannot explain the degree of fusion suppression. Therefore, an additional, more important mechanism must be involved. Here, I will present an innovative experimental approach to investigate the mechanisms leading to complete fusion suppression in reactions of 7Li + 209Bi. Using a detector array with large angular coverage and high granularity, we measured the full distribution in energy and angle of the light reaction products associated with particular incomplete fusion products. We show that the majority cannot be produced by breakup followed by capture, and instead result from triton cluster transfer. Our results indicate that the suppression of complete fusion is primarily a consequence of innate clustering of weakly-bound nuclei, rather than of breakup. I will discuss the implications of this result for studies with radioactive nuclei.
02 May

Indirect neutron-capture cross sections for the weak r-process

02 May 2019 - 1:00 PM
1200 FRIB Laboratory
NSCL Graudate Research Assistant

Rebecca Lewis

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Understanding the production of the heaviest elements requires a wealth of information on the nuclear properties of short-lived nuclei. The rapid neutron capture process (r-process) is responsible for the majority of the production of the heaviest elements. The r-process utilizes neutron-capture reactions on heavy, neutron-rich nuclei. The nuclei involved in the r-process are very neutron-rich, short-lived, and very difficult to produce, so little information is known about them. The lack of directly measured neutron-capture cross sections has led to the development of indirect techniques that can be used to reduce the uncertainty in the neutron-capture cross sections, which can vary by orders of magnitude between different calculations. The -Oslo method is one indirect technique which aims to reduce the uncertainty in the two statistical properties of the nucleus that contribute the largest sources of uncertainty in the r-process calculations: the nuclear level density (NLD) and -ray strength function (SF). Both are required to calculate a neutron-capture cross section in the Hauser-Feshbach statistical framework, along with the neutron optical model. The -Oslo method utilizes decay to populate high-energy excited states in the same nucleus that would have been formed in the neutron-capture reaction of interest. The  rays from the de-excitation are observed in the Summing NaI (SuN) detector to determine the total excitation energy of the nucleus as well as the -ray cascade to the ground state. With this information, the NLD and SF can be extracted, after normalization to other data or theoretical calculations. With experimentally constrained NLD and SF, the overall uncertainty of a neutron-capture cross section has been showed to be significantly reduced. The neutron-capture cross sections of four neutron-rich nuclei (73Zn, 70,71,72Ni) were experimentally constrained using the -Oslo method. The 73Zn(n,)74Zn data was also used to compare the constrained neutron-capture cross sections obtained from three different Hauser-Feshbach codes to determine additional sources of systematic uncertainty. The three Ni reactions were also compared to the 68,69Ni cross sections that were previously constrained using the -Oslo method. Committee Members: Sean Liddick, Dave Morrissey, Paul Mantica, Artemis Spyrou. Thesis is on display in the Atrium.
03 May

Collinear laser spectroscopy with ion trap accuracy – Future perspectives for atomic and nuclear physics and metrology applications

03 May 2019 - 11:00 AM
1200 FRIB Laboratory
TU Darmstadt

Kristian Konig

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Focusing on highest precision, a collinear laser spectroscopy apparatus was designed and set up at TU Darmstadt. After a dedicated commissioning phase, the first experiments were performed which look very promising: Measurements on all stable Ba+ ions were conducted with a determination of rest-frame transition frequencies [1] that represent to our knowledge the most-precise collinear laser spectroscopic experiment realized so far and can even compete with modern ion trap measurements on dipole-allowed transitions. Due to the high accuracy and the direct link to frequency measurements, collinear laser spectroscopy even becomes interesting for metrology applications like the direct high-voltage evaluation [2]. The results and the means and methods for achieving very high precision will be presented including a detailed discussion of the applied laser stabilization schemes as well as the ion production, transport and superposition procedures. Future perspectives for precise a nd accurate measurements of atomic and nuclear properties at this setup and in particular collinear laser spectroscopy on helium-like light ions will be presented, which is of great interest from a nuclear structure perspective. [1] Ph. Imgram, K. König, J. Krämer, T. Ratajczyk, R. A. Müller, A. Surzhykov, and W. Nörtershäuser, Collinear laser spectroscopy at ion-trap accuracy: Transition frequencies and isotope shifts in the 6s 2S1/2 -> 6p 2P1/2,3/2 transitions in Ba+, Phys. Rev. A 99 (2019), 012511. [2] J. Krämer, K. König, Ch. Geppert, P. Imgram, B. Maaß, J. Meisner, E. W. Otten, S. Passon, T. Ratajczyk, J. Ullmann, and W. Nörtershäuser, High voltage measurements on the 5 ppm relative uncertainty level with collinear laser spectroscopy, Metrologia 55, 268 (2018)
03 May

Reaction Mechanism Dependence of the Population and Decay of 10He

03 May 2019 - 2:00 PM
1200 FRIB Laboratory
NSCL Graduate Assistant

Han Liu

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COMMITTEE: Michael Thoennessen(Chairperson), Edward Brown, Hironori Iwasaki, James Linnemann,Filomena Nunes. Thesis is on display in 1312 BPS bldg. and the NSCL atrium
09 May

Characterizing the Quark-Gluon Plasma at the CERN Large Hadron Collider

09 May 2019 - 4:00 PM
1200 FRIB Laboratory
CERN

Tapan Nayak

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For only a few millionths of a second after the Big Bang, our universe consisted of a hot and dense soup of quarks and gluons, which cooled down very quickly to form protons, neutrons, and other such normal nuclear matter. The discovery and characterization of this new phase of matter called the quark-gluon plasma (QGP), require the creation of a sufficiently large and extended volume of hot and dense matter, which is possible by colliding heavy-ions at ultra-relativistic energies. The Large Hadron Collider (LHC) at CERN, commissioned in the year 2009, has collided proton-proton, proton-lead, xenon-xenon and lead-lead collisions at unprecedented energies. The ALICE (A Large Ion Collider Experiment) collaboration at the LHC has carried out a comprehensive study of the majority of particles emitted in these collisions to study the quantum chromodynamics (QCD) phase transition and to characterize the QGP phase. In the presentation, I will discuss the recreation of the baby universe in the laboratory at the LHC and the future program.
10 May

Applications of Quantum Computing to Many-Body Nuclear Physics

10 May 2019 - 10:00 AM
1200 FRIB Laboratory
NSCL Graduate Student Assistant

Benjamin Hall

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COMMITTEE: Morten Hjorth-Jensen (Chairperson),A. Bazavov, S. Bogner, M. Hirn, D. Lee, J. Pollanen
10 May

Violin and piano concert featuring the DiaZhao Duo

10 May 2019 - 5:30 PM
1300 FRIB Laboratory
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Daniela Diaz (violin) and Qian Zhao (piano) started collaborating as the DiaZhao Duo in 2015 as students at Michigan State University (MSU), where they currently continue to pursue their careers in violin performance and collaborative piano, respectively. The DiaZhao Duo made its Carnegie Hall debut in March 2018 as First Prize Winners of the 2018 “Golden Classical Music Awards Recital.” Qian and Daniela follow the idea of promoting the violin and piano repertoire as an essential form of chamber music to create engaging and valuable experiences for diverse audiences. Born in Shenyang, China, Qian Zhao’s musical talent was already discernible at age four. She is now a graduate assistant of the at MSU, where she studies with Professor Zhihua Tang and Professor Derek Polischuk. In fall 2019, Venezuelan violinist Daniela Diaz will continue her education at MSU, as a graduate assistant in the Master of Music in Violin Performance program, under the mentorship of Professor Dmitri Berlinsky. She performs on an instrument made in 2016 by Paul Becker, kindly on loan from Carl Becker and Son.
20 May

Plasma Spectroscopy Techniques for Diagnosing Plasmas in High Energy Density, Pulsed-Power Accelerators

20 May 2019 - 2:00 PM
2025 FRIB Laboratory
Sandia National Laboratories

Mark D. Johnston

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Pulsed power devices rely on the ability to deliver high voltages and currents to a variety of complex loads with minimal transmission losses. The Z Machine at Sandia National Laboratories can deliver up to 26MA within ~100 nanoseconds to multiple physics targets. This type of current flow combined with MeV potentials across millimeter A-K vacuum gaps lead to a variety of extreme electrode heating conditions, which liberate both surface and entrained gases, forming plasmas that propagate into the vacuum gap and draw current from the load. Losses of up to 20% have been observed on Z for certain load configurations. An effort is underway to investigate plasma generation in the power flow regions of the Z Machine. Visible plasma spectroscopy is employed to spatially and temporally determine plasma formation and propagation, and to measure plasma parameters such as densities and temperatures. In addition to plasma parameters, measurements of magnetic and electric fields by Zeeman splitting and Stark shifts, respectively, are also conducted [1]. Measurements are made using multifiber arrays, input into streak and fast-gated spectrometers. Line shape analyses are performed using detailed, time-dependent, collisional-radiative (CR) and radiation transport modeling. Recent results will be discussed. [1] S. Biswas, M.D. Johnston, et. al., “Shielding of the Azimuthal Magnetic Field by the Anode Plasma in a Relativistic Self-Magnetic-Pinch Diode,” Physics of Plasmas, 25, 113102 (2018). *Sandia National Laboratories is a multimission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.
21 May

MIAZMA or the devil's stone: a physics game development project in Atomki

21 May 2019 - 2:00 PM
1400 Biomedical and Physical Sciences Building
MTA Atomki, Debrecen, Hungary

Zsolt Fulop

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MIAZMA or the Devil's Stone was created by award-winning Hungarian game developer Private Moon Studios in the framework of the project Distribution of Atomki's scientific results. Our hero arrives in Debrecen for a long weekend, not suspecting that his planned leisure trip will become an investigation for a missing boy and a most peculiar meteorite. It is for him to discover what the devilish "thunderbolt" hides: a huge diamond, an elixir of immortality or an unknown, destructive substance. MIAZMA features a great story and dozens of puzzles to solve, most of them related to the science of physics. The game, being an edutainment product, offers learning while playing. Controlling the main character, you rely on the virtual help of Atomki's scientists and instruments, and put into action your basic knowledge in physics. The game takes you to real locations with live-action cinematic approach. It lets you explore some of the main attractions in Debrecen and the laboratories of Atomki, getting a glimpse of the work going on in a nuclear research institute.
28 May

Development of SC-QWR and cryomodule for low-beta ion accelerator at RIKEN

28 May 2019 - 11:00 AM
1200 FRIB Laboratory
RIKEN Nishina Center

Naruhiko Sakamoto

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Since 2014, development of superconducting quarter-wave resonator (SC-QWR) with its resonant frequency of 75.5 MHz was performed. The SC-QWR which operates at 4 K is designed for ion acceleration with an optimum beta of 0.08. We succeeded to develop one SC-QWR with Q of 2.3E9 at an acceleration gradient 4.5 MV/m. After the study of surface treatment, the cavity was integrated to a prototype cryomodule which is capable to contain two SC-QWRs. The cryomodule is equipped with a thermal shield which is cooled by a cryocooler. The cavity was cooled by liquid helium transferred from a dewar. A coaxial probe-type RF fundamental power coupler, together with the cavity, was developed to transmit RF power of 5 kW. In this seminar development of a SC-QWR, design of the prototype cryomodule and result of rf test will be discussed. Construction of superconducting RIKEN linac, so-called SRILAC, is underway for the experiments of new super-heavy-element synthesis. The SRILAC consists of three cryomodules based on ten SC-QWRs with an operation frequency of 73.0 MHz. The fabrication and surface treatment of the SC-cavities were performed in basically the same way. Results from acceptance tests of these cavities and construction status will be also reported.
03 Jun

2019 International Conference on Proton-Emitting Nuclei - (PROCON 2019)

03 June 2019 - 8:30 AM
1300 FRIB Laboratory
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The 2019 International Conference on Proton-Emitting Nuclei (PROCON2019) is the 6th in a series of conferences whose aim is to review recent experimental and theoretical progress on the properties of proton-rich nuclei.
05 Jun

Quantum Monte Carlo Studies of Fermi systems in Lattice Effective Field Theory

05 June 2019 - 11:00 AM
1200 FRIB Laboratory
Graduate Student Assistant, NSCL

Rongzheng He

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Committee: Dean Lee (Chairperson), Alexei Bazavov, Norman Birge, Heiko Hergert, Witold Nazarewicz. Thesis is on display in 1312 BPS bldg. and the NSCL atrium
05 Jun

Improved Search for CP Violation in Ortho-Positronium Decay

05 June 2019 - 2:00 PM
1200 FRIB Laboratory
Graduate Student Assistant, NSCL

Tom-Erik Haugen

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Committee: Oscar Naviliat-Cuncic (Chairperson), J. Huston, G. Severin, J. Singh, A. Von Mateuffel
05 Jun

Fission in exotic nuclei using density functional theory

05 June 2019 - 3:00 PM
1200 FRIB Laboratory
Graduate Assistant, NSCL

Zachary Matheson

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Committee: Witold Nazarewicz(Chairperson),Shanker Balasubramaniam, Matthew Hirn,William Lynch Filomena Nunes. Thesis is on display in 1312 BPS bldg. and the NSCL atrium
06 Jun

Semi-Analytic Model for Intense Beam Instabilities in Rings”

06 June 2019 - 1:00 PM
1200 FRIB Laboratory
Graduate Student Assistant, NSCL

Michael Balcewicz

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Committee: Yue Hao (Chairperson), S. Lidia, S. Lund, M. Maghrebi, S. Pratt
07 Jun

Factorization Methods for Similarity Renormalization Group

07 June 2019 - 11:00 AM
1200 FRIB Laboratory
Graduate Student, NSCL

Boyao Zhu

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Committee: Heiko Hergert(Chairperson), S. Bogner M. Hirn, M. Iwen, S. Liddick
20 Jun

State of the art mass spectrometry for nuclear science at TITAN

20 June 2019 - 2:00 PM
1200 FRIB Laboratory
University of British Columbia

Erich Leistenschneider

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The atomic mass is a crucial property to understand the nature of nuclear forces, nuclear structure, fundamental symmetries, and astrophysical processes. The TITAN facility at TRIUMF has been successfully performing precision mass measurements of radioactive nuclei for over a decade. In a recent result, the emergence of nuclear shell effects in N=32 was studied in neutron-rich Ti and V isotopes. The very sensitive TITAN Multiple Reflection Time-of-Flight Mass Spectrometer enabled the mass measurements of ions of interest in highly contaminated ion samples. The results conclusively establish the existence of weak shell effects in titanium but no effect in vanadium, narrowing down the abrupt onset of this shell closure. As this experiment illustrates, mass spectrometry techniques have become more challenging as the availability of beams grows towards increasingly exotic species. They need to be faster for shorter lifetimes, more sensitive for lower intensities, higher resolving for larger contamination levels, and sufficiently precise for scientific interest. Recent developments at TITAN have been demonstrated or are being commissioned. Among them, upgrades in the TITAN's Penning Trap Mass Spectrometer will push the precision boundary towards the parts-per-billion level for species living as short as a few tens of milliseconds. In this seminar, I will discuss some of TITAN's recent measurements, aspects of the technical advances, and plans for future developments.
26 Jun

Residual nuclei production in fragmentation and fission reactions investigated in inverse kinematics

26 June 2019 - 4:00 PM
1200 FRIB Laboratory
University of Santiago de Compostela

Jose Fernando Benlliure-Anaya

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The nature of the final fragments produced in nuclear reactions has been widely used to obtain valuable information on the reaction mechanism, but also on the bulk or structural properties of the reacting nuclei. The understanding of the final yields is also of utmost importance in many applications such as radiotherapy, radioprotection or the beams delivered by radioactive beam facilities. In this talk I will present some of the results obtained during the last decade at GSI investigating the fragment yields produced in fragmentation and fission reactions using inverse kinematic reactions at relativistic energies. I will also address some future plans at GSI/FAIR.
27 Jun

Charge Radii of Sc Isotopes and Precise Calibration of Laser Frequency

27 June 2019 - 11:00 AM
1200 FRIB Laboratory
NSCL Graduate Assistant

Robert Powel

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A kink structure is observed at all the magic numbers in chains of charge radii but is missing at the neutron number N = 20 for 18Ar, 19K and 20Ca. Charge radii of neutron-deficient 21Sc across N = 20 are planned to be determined to address the disappearance of shell-closure signature. Collinear laser spectroscopy technique will be used, which requires accurate knowledge of laser frequency, to deduce the charge radii. To calibrate laser frequency, a Doppler-free spectroscopy system on iodine molecule is being implemented to use accurately-known transitions in the visible to near-infrared light. Techniques used and the current development status will be discussed. Committee: Kei Minamisono(Chairperson), T. Cocker H. Hergert, R. Ringle, S. Tessmer
27 Jun

Tentative Thesis Title: Fission in the Pb region”

27 June 2019 - 3:00 PM
1200 FRIB Laboratory
NSCL Graduate Assistant

Adam Anthony

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COMMITTEE: William Lynch (Chairperson),D. Bazin H. Lin, W. Nazarewicz, M. Tsang
28 Jun

Computational developments for Ab Initio many-body theory

28 June 2019 - 10:00 AM
1200 FRIB Laboratory
NSCL Graduate Assistant

Justin Lietz

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Committee: Morten Hjorth-Jensen (Chairperson), Alexei Bazavov, Scott Bogner, Alexandra Gade, Brian O’Shea. Thesis is on display in 1312 BPS bldg. and the NSCL atrium
09 Jul

What happens when two nucleons get very close to each other?

09 July 2019 - 11:00 AM
1200 FRIB Laboratory
Racah Institute of Physics

Ronen Weiss

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Nuclear short-range correlations (SRCs), i.e. the probability of finding few nucleons close to each other inside the nucleus, are an integral part of the description of nuclear systems, important also for neutrons-star structure and for the bound nucleon structure function. To study the implications of such correlations, we use a new theoretical tool, called the generalized contact formalism. In this talk I will present the original contact formalism, designed for atomic systems, and our generalization to nuclear systems. Using this formalism, we have been able to identify and quantify the effects of two-body SRCs on various nuclear quantities. Among these quantities are the one-body and two-body momentum distributions, the photo-absorption cross-section analyzed by Levinger using the quasi-deuteron model, and the Coulomb sum-rule. Most of our predictions were verified experimentally or numerically. Recently,analyzing the nuclear spectral function, we were also able to utilize the contact formalism to study exclusive electron scattering experimental data, which is one of the main experimental tools for studying SRCs. I will present direct comparison with experimental data and possible implications to the description of dense nuclear matter with nucleonic degrees of freedom.
09 Jul

Theory and modeling of intense ion beams and diagnostic measurements in accelerator front ends

09 July 2019 - 12:30 PM
1200 FRIB Laboratory
NSCL Graduate Assistant

Chun Yan Jonathan Wong

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COMMITTEE: Steven Lund (Chairperson), Phillip Duxbury, Yue Hao, Peter Ostroumov, Vladimir Zelevinsky Thesis is on display in 1312 BPS bldg. and the NSCL atrium
10 Jul

Tentative Thesis Title: Total absorption spectroscopy and neutron star cooling

10 July 2019 - 11:00 AM
1200 FRIB Laboratory
NSCL Graduate Assistant

Kirby Hermansen

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COMMITTEE: Hendrik Schatz (Chairperson), S. Couch W. Fisher, M. Hjorth-Jensen, A. Spyrou
11 Jul

Precision measurements of beta-energy spectrum in 6He decay

11 July 2019 - 11:00 AM
1200 FRIB Laboratory
NSCL Graduate Assistant

Xueying Huyan

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COMMITTEE: Oscar Naviliat-Cuncic(Chairperson), Kei Minamisono, Wayne Repko, Stuart Tessmer, Vladimir Zelevinsky. Thesis is on display in 1312 BPS bldg. and the NSCL atrium
11 Jul

Fundamental Capture Processes with Ion and Electron Beams

11 July 2019 - 2:00 PM
1200 FRIB Laboratory
Western Michigan University, Jagiellonian University

David La Mantia

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Electron capture to ions is of central importance for the physics of all plasmas. This is especially true for astrophysical plasmas, as the vast majority of atomic matter in the universe consists of ions and electrons. These capture processes often result in the emission of radiation, either directly or through associated excitation and relaxation of bound electrons in the ion. That radiation is a key diagnostic tool for the composition of the plasma and the processes taking place therein. In the laboratory, ions can be created and employed in many ways to explore fundamental processes. Electrostatic accelerators have been in operation around the world for well over 80 years and are a powerful tool for this purpose. The tandem van de Graaff accelerator at WMU is such a device capable of low- to mid-Z, relatively low-energy acceleration. Single photon emission accompanying two-electron capture can be considered the time inverse of double photoionization, a process sparsely studied for two-electron systems other than helium, and was proposed theoretically over 30 years ago. This process is referred to as radiative double electron capture and has now been observed for the first time in gas targets at WMU using F9+ and F8+ swift projectiles and coincidence timing techniques. More recently (in the last 30 years), electron beam ion traps have been used to create and manipulate ions. The EBIT at JU is a compact, room-temperature trap capable of creating fully-stripped argon, the species of interest here, as well as other ions. The detection of emitted radiation allows the exploration of plasma dynamics within the trap, with attention given to charge-state distribution and evolution. Evidence has been found of high-order resonances in the plasma using electron beams beyond the dielectronic recombination limit.
15 Jul

Probing proton cross-shell excitations for Ni-70 using nucleon knockout reactions

15 July 2019 - 9:00 AM
1200 FRIB Laboratory
NSCL Graduate Assistant

Brandon Elman

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Committee: Alexandra Gade (Chairperson), B. Alex Brown, Carlo Piermarocchi, Jaideep Singh, Michael Thoennessen Thesis is on display in 1312 BPS bldg. and the NSCL atrium
16 Jul

Precision measurements in 20F beta decay

16 July 2019 - 1:00 PM
1200 FRIB Laboratory
NSCL Graduate Assistant

Manimilian Nathan Hughes

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COMMITTEE: Oscar Naviliat-Cuncic (Chairperson), B. Alex Brown, Wade Fisher, Kei Minamisono, Jaideep Singh. Thesis is on display in 1312 BPS bldg. and the NSCL atrium
23 Jul

Mg-20 beta-decay and the O-15 (alpha,gamma), Ne-19 (p,gamma), Na-20 reaction sequence in type I x-ray bursts

23 July 2019 - 1:00 PM
1300 FRIB Laboratory
NSCL Graduate Assistant

Brent Glassman

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Committee: Chris Wrede (Chairperson), Heiko Hergert, Hironori Iwasaki, Jim Linnemann, Artemis Spyrou. Thesis is on display in 1312 BPS bldg. and the NSCL atrium
30 Jul

Charged pion emission from 112Sn + 124Sn and 124Sn + 112Sn reactions with the S&pi;RIT time projection chamber

30 July 2019 - 9:30 AM
1200 FRIB Laboratory
NSCL Graduate Assistant

Jonathan Elijah Barney

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Committee: William G. Lynch (Chairperson), Edward Brown, Pawel Danielewicz, Stuart Tessmer, Manyee Betty Tsang. Thesis is on display in 1312 BPS bldg. and the NSCL atrium
30 Jul

Measurements of charge radii of neutron-deficient calcium using collinear laser spectroscopy at becola

30 July 2019 - 3:00 PM
1200 FRIB Laboratory
NSCL Graduate Assistant

Andrew Jacob Miller

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Committee: Kei Minamisono (Chairperson), Matthew Comstock, Paul Mantica, Jaideep Singh, Witold Nazarewicz. Thesis is on display in 1312 BPS bldg. and the NSCL atrium
01 Aug

Particles correlation function in heavy-ion collisions

01 August 2019 - 4:00 PM
1200 FRIB Laboratory
NSCL Graduate Assistant

Pierre Nzabahimana

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Committee: Pawel Danielewicz (Chairperson), F. Nunes, C. Piermarocchi, S. Pratt, M. Tsang.
05 Aug

Perturbative measurements of electron cyclotron resonance ion source plasmas

05 August 2019 - 10:00 AM
1300 Biomedical and Physical Sciences Building
NSCL Graduate Assistant

Derek Elwin Neben

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Committee: Guillaume Machicoane (Chairperson), Norman Birge, Daniela Leitner, Steven Lund, John Verboncoeur. Thesis is on display in 1312 BPS bldg. and the NSCL atrium
05 Aug

Tentative thesis title: High-precision mass measurement of 24Si and the construction of the molecular breaker (MoB)

05 August 2019 - 3:30 PM
1200 FRIB Laboratory
NSCL Graduate Assistant

Daniel Puentes

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Committee: Georg Bollen (Chairperson), J. Huston S. Liddick, M. Maghrebi, R. Ringle, L. Roberts.
16 Aug

Fostering the art of scientific discovery in gifted children

16 August 2019 - 5:30 PM
1300 FRIB Laboratory
Bulgarian Academy of Sciences

Evgenia Sendova

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This talk will be a patchwork of personal stories highlighting the speaker's constructionist teaching experiences, going back to her roots in Bulgaria and supplemented by an over 20-year involvement with two institutions helping gifted high-school students engage in scientific research. The first is the Research Science Institute, organized by the Center for Excellence in Education, in collaboration with the Massachusetts Institute of Technology (MIT). The second is the High School Institute of Mathematics and Informatics in Bulgaria.
23 Aug

Tentative Thesis Title: Ab-Initio Nuclear Theory: From Nuclei to Neutron Stars

23 August 2019 - 11:00 AM
1300 FRIB Laboratory
NSCL Graduate Assistant

Omokuyani Udiani

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Committee: Scott Bogner (Chairperson), E. Brown M. Hirn, M. Hjorth-Jensen, D. Lee
04 Sep

Beta-delayed proton decay in neutron-rich nuclei

04 September 2019 - 4:10 PM
1200 FRIB Laboratory
Michigan State University

Yassid Ayyad

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Nuclei with more neutrons than protons tend to get rid of excess neutrons to reach the valley of stable nuclei through beta-minus decays. On the other side of the valley of stability, proton-rich nuclei follow the analogous process through beta-plus decays. Beta-delayed proton emission, observed more than 40 years ago, typically occurs in very proton-rich nuclei and not on the neutron-rich side of the stable nuclei. However, the emission of protons following beta-minus decay is energetically allowed for neutron-rich nuclei with neutrons bound by less than 782 keV. This condition may be fulfilled in so-called halo nuclei where one or several neutrons are loosely bound and orbit far from the core. 11Be is one of the most promising candidates, resulting in 10Be following the beta decay to 11B and the subsequent proton emission. A team of NSCL (National Superconducting Cyclotron Laboratory, Michigan State University, USA) and TRIUMF (Canada) researchers carried out the first direct observation of the beta-delayed proton decay of a neutron-rich nucleus by directly measuring the very low-energy protons emitted following the beta decay of 11Be. This experiment was performed with the Active Target Time Projection Chamber (AT-TPC), a gas-filled detector capable of providing high efficiency and resolution for low-energy charged particles such as the emitted protons. In this seminar, I will discuss the technique and the results of such experiment, as well as different aspects of this decay, including a speculative dark matter decay.
05 Sep

Results from harvesting experiments at NSCL

05 September 2019 - 11:00 AM
1200 FRIB Laboratory
Michigan State University

Greg Severin

09 Sep

Constraining the Dense-Matter Equation of State with Neutron Star Mergers

09 September 2019 - 12:30 PM
1400 Biomedical and Physical Sciences Building
University of Arizona

Carolyn Raithel

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Observations of neutron stars provide one of the best ways of probing the ultra-dense matter equation of state (EOS). While X-ray measurements of the neutron star radius have provided some promising constraints on the EOS, uncertainties remain at high densities. Detections of gravitational waves from a binary neutron star merger(s) offer an exciting, complementary approach to constraining the EOS. In this talk, I will discuss how we can directly extract stellar radii from gravitational wave events. In particular, I will explore the surprising relationship has been discovered between the binary tidal deformability and the radius. I will compare the radius constraints from GW170817 to existing radii measurements from X-ray observations and discuss the implications for the EOS. Finally, I will discuss how we can use gravitational wave events to constrain the properties of the nuclear symmetry energy, motivated by the well-established connection between the stellar radius and the slope of the symmetry energy, L.
10 Sep

Microscopic optical potentials from chiral nuclear forces

10 September 2019 - 11:00 AM
1200 FRIB Laboratory
Texas A&M University

Jeremy Holt

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We formulate microscopic optical potentials for nucleon-nucleus scattering from chiral two- and three-nucleon forces. The real and imaginary central terms of the optical potential are obtained from the nucleon self-energy in infinite nuclear matter at a given density and isospin asymmetry, calculated self-consistently to second order in many-body perturbation theory. We compare the microscopic results for proton scattering on 40,42,44,48Ca to those of phenomenological models and experimental data up to projectile energies of E = 180 MeV. While overall satisfactory agreement with the available experimental data is obtained, we find that the elastic scattering and total reaction cross sections can be significantly improved with a weaker imaginary optical potential, particularly for larger projectile energies.
11 Sep

Hot and dense neutron-rich matter in supernovae and neutron star mergers

11 September 2019 - 4:10 PM
1200 FRIB Laboratory
Texas A&M University

Jeremy Holt

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Recently, the first confirmed observation of a binary neutron star merger through its gravitational wave (GW170817) and associated electromagnetic emissions has opened a new window into our understanding of ultra-dense matter. Supercomputer simulations of these events relies on detailed knowledge of the equation of state, transport and linear response properties of hot and dense neutron-rich matter. In this talk I will describe recent progress in modeling the strong interaction physics of neutron stars and supernovae based on the low-energy realization of QCD, chiral effective field theory. I will demonstrate how our present understanding of nuclear physics is already consistent with the gravitational wave signal from GW170817 but that there are strong prospects for stronger constraints from upcoming observational campaigns of neutron stars.
12 Sep

Collective neutrino oscillations on a quantum computer

12 September 2019 - 11:00 AM
1200 FRIB Laboratory
Michigan State University

Ben Hall

18 Sep

Physics of Multi-Bend Achromat Lattice

18 September 2019 - 4:10 PM
1200 FRIB Laboratory
Argonne National Laboratory

Ryan Lindberg

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Storage ring light sources around the world provide intense x-rays for science, and yet there are still a host of experiments that require higher x-ray flux and brightness. One way to meet this demand is with a storage ring that employs a multi-bend achromat (MBA) lattice, which can increase the electron beam brightness and thereby the x-ray brightness by two orders of magnitude. Along with this great potential comes great challenges for storage ring design, including the requirements of strong magnets with small vacuum apertures, the demands of tight error tolerances, and the difficulty of controlling highly nonlinear dynamics. I will discuss how these challenges are being addressed with a combination of clever design, improvements in technology, and advanced simulation and optimization techniques. I will illustrate these examples with a number of MBA projects around the world, with a central focus on the planned upgrade at the Advanced Photon Source.
19 Sep

Highlights in Progress

19 September 2019 - 11:00 AM
1200 FRIB Laboratory
Michigan State University

Kellen McGee & Aldric Revel

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Doubling FRIB energy: First test results of a new superconducting medium-beta accelerating cavity; Extending the South Shore of the Island of Inversion to 28F
23 Sep

JINA-CEE Science Cafe: Supernovae (link is external)

23 September 2019 - 1:30 PM
1400 Biomedical and Physical Sciences Building
NSCL, Physics and Astronomy

Kirby Hermansen, Chelsea Harris

24 Sep

The challenge of discovering QCD critical point

24 September 2019 - 11:00 AM
1200 FRIB Laboratory
University of Illinois

Mikhail Stephanov

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Quantum Chromodynamics predicts a variety of unusual states of matter in which relativity and quantum many-body physics strongly intertwine. Discovering phase transitions between these hottest and densest forms of matter in a laboratory is an unprecedented task. This is the challenge that heavy-ion collision experiments are taking up in the Beam-Energy Scan program at the Relativistic Heavy-Ion Collider (RHIC). What do we know about the phase diagram of QCD matter and how do we learn more? One of the intriguing open questions is the existence and the location of the QCD critical point. Similar critical points are ubiquitous in earthly substances and the phenomena associated with those points are remarkably universal. How can we use this universality to discover the critical point in QCD? It is a nontrivial question in the context of heavy-ion collisions, in large part because of the importance of non-equilibrium dynamics -- the subject of current research.
25 Sep

Protoacoustics - Validation of proton range verification system for monitoring cancer treatments

25 September 2019 - 4:10 PM
1300 FRIB Laboratory
University of Pennsylvania

Steven Avery

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An increasingly popular method for cancer treatment is proton radiation. Relative to conventional x-ray therapy, proton therapy is advantageous because protons have a limited range, called the Bragg peak (BP), which spares distal normal tissues. Despite its specificity, proton therapy carries some risk. For example, when there is an error in the range and the radiation under- or over-shoots, a drastically different dose is delivered. Due to this risk, a critical need exists to verify the proton range. Due to range uncertainty, proton treatment plans do not take full advantage of the proton's sparing capabilities. This becomes a clinically challenging issue, especially in deep seated tumors. For example, in the Central Nervous System (CNS) there are many organs at risk (OARs) such as the optic nerves, optic chiasm, brainstem, pituitary, and cochlea which abut the target site. Our application is focused on Protoacoustics, is the measurement of acoustic waves generated by clinical proton beams. Measurement of the arrival time of these kHz signals provides a simple and inexpensive method for real-time, in vivo monitoring of proton irradiation. Herein, we propose to develop a protoacoustic method for monitoring proton range in vivo by measuring the time-of-flight (TOF) of the pressure wave. We have discovered a novel role that applies this thermo-acoustic phenomenon to proton range-verification. The successful development of protoacoustic range-verification will provide greater confidence in proton range and consequently allowing smaller margins, improved sparing of healthy tissue and improved patient outcomes to build the foundation for Protoacoustics as a method for changing how proton therapy is monitored with improved targeting and decreased side effects.
26 Sep

Constraining electron-capture rates in core-collapse supernovae through charge-exchange reactions

26 September 2019 - 11:00 AM
1200 FRIB Laboratory
Michigan State University

Remco Zegers

27 Sep

Advanced Studies Gateway event: Piano concert featuring Frederick Isaac

27 September 2019 - 5:30 PM
1300 FRIB Laboratory
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As a composer with many writing interests, Frederick Isaac’s preferred mediums include solo piano, classical chamber ensembles, jazz trios, electronic/computer-generated, and vocal. He is just as comfortable working in varying musical styles and languages, from tonal to the avant-garde, as demonstrated by many of his recordings. Isaac’s professional career began as a drummer when he was just sixteen. Currently a college music professor by day, he spent more than two decades producing music for musical theater, church choirs, cocktail bars, jazz ensembles, salsa bands, and ballet companies, both as a pianist/drummer and director. These experiences included stints working for music legend Ben E. King and the Joffrey Ballet of New York. Along with establishing his own label, he is currently included on a few others, including Music Box Classics. In the past several years, his solo piano recordings have gained airplay on college and internet radio stations. These services include Pandora, Sky FM, Calm Radio, MPR, and WKAR FM.
28 Sep

FRIB Saturday Morning Physics talk: A microscopic view of the stars

28 September 2019 - 10:30 AM
1300 FRIB Laboratory
National Superconducting Cyclotron Laboratory

Stephanie Lyons

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How do you attempt to understand the inner workings of an object when you can’t get close to it? In this Saturday Morning Physics talk, Stephanie Lyons will discuss how scientists at FRIB are working to understand some of the largest objects in the universe, using some of the smallest. In a celebration of the International Year of the Periodic Table, Lyons will take the audience on an adventure to the interior of a star to understand how the elements are made. This talk will dive into understanding the role that nuclear physics plays in the cosmos, and how experiments in the laboratory help answer major scientific questions. This talk is a part of FRIB Saturday Morning Physics.
30 Sep

Weighing a ghost: Horizons on neutrino mass probes

30 September 2019 - 2:00 PM
1200 FRIB Laboratory
University of Washington

Walter Pettus

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The ghostly neutrinos remain the only fundamental fermions whose masses are unknown. The very existence of their mass is a breach in the Standard Model of Particle Physics, and the scale of their mass - six orders of magnitude lighter - sets them apart from the other fermions. Yet information about the neutrino mass is imprinted on the universe across all scales - from the grand cosmic down to the particle. In this seminar I will highlight two nuclear physics experimental programs which will advance our sensitivity to the mysteries of the neutrino. Project 8 will probe the neutrino mass scale through direct kinematics of the tritium beta spectrum endpoint. LEGEND will probe the potential Majorana character of the neutrino by searching for neutrinoless double beta decay of 76Ge. Both programs offer next-generation sensitivity with the potential to investigate neutrino mass at or below the inverted hierarchy scale.
02 Oct

The road goes ever on: status and prospects for nuclear science at Los Alamos Neutron Science Center (LANSCE)

02 October 2019 - 4:10 PM
1200 FRIB Laboratory
Los Alamos National Laboratory

Shea Mosby

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Neutron-induced reactions are a topic of general interest in nuclear technology and nuclear astrophysics. Neutron capture and neutron-induced fission are of particular interest, and we have at the Los Alamos Neutron Science Center (LANSCE) a diverse research program addressing these questions for stable and long-lived nuclei. As we look to the future of nuclear reaction measurements, increasing demand for reaction rates on short-lived nuclei where traditional direct techniques fail is driving us to consider an entirely new approach. The approach, which we've dubbed MORD0R, would couple a heavy ion storage ring to a "neutron target" driven by a spallation neutron source in order to directly measure neutron-induced reactions in inverse kinematics. The status of our current research program at LANSCE will be presented, and results from our ongoing feasibility studies for MORD0R discussed.
03 Oct

DNP practice talks

03 October 2019 - 11:00 AM
1200 FRIB Laboratory
Michigan State University

J. Ash; J. Lantis; M. Grinder; R. Elder; J. Schmitt; K. Childers; R. Powel

Show/Hide Abstract
High-spin States and Cross-shell Excitations in 46Ca; Electron Population Manipulation of Transition Metal Isotopes in an RFQ Ion Trap; Precision Lifetime Measurements of Excited States in 38Si; Probing Large Collectivity in Mg-32 with a Recoil-distance Lifetime Measurement; Probing Spin-Isospin Excitations in Proton-Rich Nuclei via the (p,n) Reaction; Constraining the cross section of 82Se(n,g)83Se to validate the beta-Oslo method; Precise Calibration of Laser Frequency for determination Sc Charge Radii
07 Oct

JINA-CEE Science Cafe: Mental wellbeing in academia (link is external)

07 October 2019 - 2:00 PM
1400 Biomedical and Physical Sciences Building
MSU Physics and Astronomy

Abbie Stevens

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Mental health can take many forms and people who work in high-stress environments are prone to experience mental health issues. There is a mental wellbeing crisis in academia, one that has been documented in multiple recent studies of graduate students. Even worse, gender, racial/ethnic, and sexuality minorities experience mental health problems at higher rates. Problems (and their solutions) exist, both at individual and community levels, though triggers can be difficult to identify and resources can be difficult to find and access. This talk will be a starting point for conversations about mental wellbeing as it pertains to astronomers and physicists at MSU, and as mental health issues can and do affect people at all career levels, everyone from students to professors are encouraged to attend.
08 Oct

Supernova nucleosynthesis

08 October 2019 - 11:00 AM
1200 FRIB Laboratory
University of Minnesota

Andre Sieverding

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Core-collapse supernovae mark the death of massive stars and are important sites of nucleosynthesis. The recent decades have brought great progress in our understanding of the supernova mechanism with implications for the production of the elements. In this talk I will discuss open questions and recent progress in understanding supernova nucleosynthesis with particular focus on the supernova neutrino process and the role of multi-dimensional simulations.
09 Oct

Superheavy elements: Making and breaking the periodic table

09 October 2019 - 4:10 PM
1200 FRIB Laboratory
Bloomsbury Sigma

Kit Chapman

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The thrilling history of creating elements past uranium - from the first steps during the Manhattan Project to the modern experiments rewriting our understanding of the chemical world. From flying planes into mushroom clouds to some of the most powerful research machines in the world, this will reshape everything you think you know about scientific discovery.
11 Oct

Structure and neutron decay of the most neutron-rich beryllium isotopes

11 October 2019 - 1:00 PM
1200 FRIB Laboratory

Belen Monteagudo Godoy

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The study of neutron-rich nuclei provides a powerful insight on nuclear structure and its evolution towards extreme configurations. Unusual properties and new exotic decay modes are encountered as we move further away from stability. Near the dripline, where the energy needed to remove one nucleon is low enough or even negative, neutron emission from neutron-rich nuclei is a characteristic phenomenon. Ground state two-neutron decays are a special case that may occur once we go beyond the dripline. So far, and since the neutron dripline is only attainable for light nuclei, only two clear candidates are found:26O[1] and 16Be[2]. With this aim, we have investigated the spectroscopy and neutron decay of the most neutron-rich isotopes of Beryllium, 14Be, 15Be and especially 16Be, during different experimental campaigns at RIBF- RIKEN using the SAMURAI setup and the NEBULA neutron array. The high beam intensities and large neutron acceptance, coupled in the 16Be case to the high luminosity and resolution provided by the MINOS target, let us probe their spectroscopy over a wide energy range with good statistics. The detailed treatment of multi-neutron events has given access to the analysis of the three-body correlations of the several core+n + n decays from the populated two-neutron unbound states. In close collaboration with theorists, the characteristic low-energy nn correlations observed have been linked to the three-body wave function and therefore, the internal correlations of those systems. In particular, the role that the n-n interaction plays in the structure of the 16Be ground state, and in its further decay, has been identified through a direct comparison of theory and experiment. The results obtained for the three Beryllium isotopes will be presented, and the perspectives opened by this work discussed. References:[1] Y. Kondo et al. Phys. Rev. Lett. 116, 102503 (2016).[2] A. Spyrou et al., Phys. Rev. Lett. 108, 102501 (2012).
15 Oct

Musical creativity and the brain

15 October 2019 - 5:30 PM
1300 FRIB Laboratory
Francis A. Sooy Professor of Otolaryngology-Head and Neck Surgery and the chief of the division of Otology, Neurotology and Skull Base Surgery at University of California, San Francisco

Charles Limb

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Musical creativity has existed since the earliest days of human civilization. Until recently, how the brain actually produces musical ideas was poorly understood. Recent advances in brain imaging have allowed us to address questions of artistic significance that were previously felt to be inaccessible to scientific inquiry. Of the multiple creative processes that take place in music, improvisation—the spontaneous generation of musical material—provides an inspiring tool to study these processes. This presentation will highlight several functional neuroimaging studies that have examined the process of musical improvisation in expert jazz and hip-hop musicians, as a window into the complex neural processes that give rise to creativity. This talk is supported in part by the Michigan State University Vice President of Research and Graduate Studies.
19 Oct

Physics girl - the collision of science and art

19 October 2019 - 2:00 PM
Wharton Center for Performing Arts

Physics Girl Dianna Cowern

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As part of the FRIB Saturday Morning Physics series, the MSU Science Communication organization (MSU SciComm) in partnership with FRIB presents its first live science-art show featuring Physics Girl. The show will be at the Wharton Center for Performing Arts. Free tickets are required for entry. The show will also be livestreamed inside the FRIB auditorium, in conjunction with the MSU SciComm science-art exhibition outside the FRIB auditorium. Other SciComm events are planned, including an FRIB virtual tour on the dome of Abrams Planetarium, and a Beat the Scientist event at The Grid Arcade and Bar.
21 Oct

Nucleosynthesis constraints through very late observations of type Ia supernovae

21 October 2019 - 12:30 PM
1400 Biomedical and Physical Sciences Building
MSU Physics and Astronomy

Wolfgang Kerzendorf

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Type Ia supernovae are likely the thermonuclear explosion of relatively massive white dwarfs. The ignition process for these normally inert objects remains a mystery. The community has identified several plausible ignition scenarios (accretion from a companion, merger of white dwarfs, compression through the explosion of a helium shell, etc.). The current plethora of viable models matches the data of the first weeks to months - making it hard to distinguish between them. In this talk, I will show that, while the current feasible models produce very similar amounts of Ni56, their Ni57 and Co55 yields can be very different. These isotopes have decay chains with half-lives of hundreds of days leading to light-curves differences in very late epochs of 500 days and more. I will discuss the work on the extremely late light-curves (>1000 days) of the very nearby SN2011fe and the challenges faced. I will conclude by discussing how JWST will provide crucial observing capabilities that will finally allow us to rule out several of the proposed models.
22 Oct

From alpha clustering to homogeneous matter

22 October 2019 - 11:00 AM
1200 FRIB Laboratory
University of Guelph

Alexandros Gezerlis

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Over the last few decades the study of nuclei and neutron-rich matter from first principles has entered a new era. This has partly been driven by the development of novel interactions between two or three nucleons. In an attempt to produce a systematic expansion, several groups have produced Effective Field Theory (EFT) interactions, whether of finite range (chiral EFT) or zero range (pionless EFT). Pionless EFT has been quite successful in studies of cold-atomic Fermi gases. In this talk, I will present recent Quantum Monte Carlo calculations of 8-particle systems and discuss their impact on 8Be and the physics of alpha clustering. I will also discuss recent work on trying to connect ab initio theory with simpler qualitative pictures. Specifically, I will address the first ever systematic non-perturbative calculations of the single-particle excitation spectrum in strongly interacting neutron matter. In addition to impacting light and neutron-rich nuclei, this work and this talk also touch upon the physics of ultracold gases and of neutron stars.
23 Oct

"Fortuitous" near-threshold resonances and the curious case of B-p+ decay of 11Be

23 October 2019 - 4:10 PM
1200 FRIB Laboratory
GANIL

Marek Ploszajczak

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Loosely bound nuclei are currently at the center of interest in low-energy nuclear physics. The deeper understanding of their properties provided by the shell model for open quantum system offers new insights into structural phenomena and provides new opportunities for spectroscopic studies for states in the vicinity of the particle emission threshold. I will review the recent progress in the open quantum system shell model description of near-threshold collectivity, clustering, and collectivization of electromagnetic transitions in near-threshold states. In particular, I will discuss the structure of the recently observed near-threshold resonance in 11B, whose very existence explains the rare beta-delayed proton emission of the neutron-rich 11Be.
23 Oct

"Fortuitous" near-threshold resonances and the curious case of B-p+ decay of 11Be

23 October 2019 - 4:10 PM
1200 FRIB Laboratory
GANIL

Marek Ploszajczak

Show/Hide Abstract
Loosely bound nuclei are currently at the center of interest in low-energy nuclear physics. The deeper understanding of their properties provided by the shell model for open quantum system offers new insights into structural phenomena and provides new opportunities for spectroscopic studies for states in the vicinity of the particle emission threshold. I will review the recent progress in the open quantum system shell model description of near-threshold collectivity, clustering, and collectivization of electromagnetic transitions in near-threshold states. In particular, I will discuss the structure of the recently observed near-threshold resonance in 11B, whose very existence explains the rare beta-delayed proton emission of the neutron-rich 11Be.
23 Oct

"Fortuitous" near-threshold resonances and the curious case of B-p+ decay of 11Be

23 October 2019 - 4:10 PM
1200 FRIB Laboratory

Marek Pl

Show/Hide Abstract
Loosely bound nuclei are currently at the center of interest in low-energy nuclear physics. The deeper understanding of their properties provided by the shell model for open quantum system offers new insights into structural phenomena and provides new opportunities for spectroscopic studies for states in the vicinity of the particle emission threshold. I will review the recent progress in the open quantum system shell model description of near-threshold collectivity, clustering, and collectivization of electromagnetic transitions in near-threshold states. In particular, I will discuss the structure of the recently observed near-threshold resonance in 11B, whose very existence explains the rare beta-delayed proton emission of the neutron-rich 11Be.
24 Oct

Dark matter research in nuclear physics

24 October 2019 - 11:00 AM
1200 FRIB Laboratory
Michigan State University

Wolfgang Mittig

25 Oct

Measuring the half-life of O-26

25 October 2019 - 9:30 AM
1200 FRIB Laboratory
NSCL Graduate Assistant

Thomas Redpath

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Committee: Michael Thoennessen(Chairperson), Alexandra Gade, Morten Hjorth-Jensen, Jaideep Singh, Elizabeth Simmons. Thesis is on display in 1312 BPS bldg. and the NSCL atrium
28 Oct

High-density cascade arc plasma sources for application to plasma windows for virtual vacuum interfaces

28 October 2019 - 4:00 PM
1309 FRIB Laboratory
Hiroshima University

Prof. Shinichi Namba

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We have developed two cascade arc plasma sources for application to plasma windows for virtual vacuum interfaces. For windowless vacuum–atmosphere separation enabling us to carry out an electron beam welding under atmospheric air condition, a compact arc discharge source having a channel diameter of 3 mm is fabricated, and an atmospheric Ar thermal plasma is generated. On the other hand, to generate a highly charged 238U65+ ion beam with a high intensity and high energy of 10.8 MeV/u in heavy ion accelerators, a He gas charge stripper target has been employed in the Radioactive-Isotope Beam Factory (RIBF) at RIKEN. Using a cascade arc plasma as a virtual window creates an effective vacuum interface to isolate the high pressure He gas cell from the lower pressure vacuum stages. Therefore, we also developed a larger diameter cascade arc discharge apparatus (channel diameter: 8 mm) for application to an alternative differential pumping system. The performances of the two cascade arcs as plasma windows are investigated. The 3-mm arc discharge generates a steep pressure gradient of Ar 100 kPa to 100 Pa through the discharge channel, while the 8-mm discharge apparatus isolates the high-pressure side at 7 kPa from the lower pressure of 54 Pa. Emission spectroscopy of visible and vacuum UV radiation reveals the characteristics of the Ar and He plasmas. Spectral analysis yields a plasma temperature of around 1 eV in both discharges. Stark broadenings of the H- and Ar I lines give an electron density of 6.5*1016 cm-3 for Ar 60 A with a gas flow rate of 1.0 L/min, and 4.7*1013 cm-3 under a He 100-A and 0.45-L/min condition.
29 Oct

Atomic nucleus an open quantum many-body system

29 October 2019 - 11:00 AM
1200 FRIB Laboratory
Florida State University

Alexander Volya

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The atomic nucleus is a natural self-binding quantum many-body system where structure and stability are governed by an intricate interplay of quantum many-body interactions and the dynamics in the nuclear reaction continuum. The atomic nucleus is an outstanding research laboratory that allows us to target the generic phenomena of finite open quantum many-body systems, such as formation of the mean field, collective and chaotic dynamics, effects of particle decay, and clustering. In this presentation I will discuss the physics of decays and reactions involving unstable nuclei and I will demonstrate how a consistent simultaneous description of many-body structure and reactions can help in resolving fundamental questions of modern science.
30 Oct

Gamma-ray spectroscopy at the limits

30 October 2019 - 4:10 PM
1200 FRIB Laboratory
Lawrence Berkeley National Laboratory

H.L. Crawford

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The study of nuclei far from stability is one of the most active and challenging areas of nuclear structure physics. Studies of the most exotic neutron-rich isotopes require an unprecedented combination of beam intensities and detection sensitivity, which will soon be realized here in the United States at the Facility for Rare Isotope Beams, with [gamma]-ray spectrometers such as GRETA. I will present an update on the status of GRETA and an outlook of the physics to be explored with this world-leading combination of beams and spectroscopic capabilities. I will begin however with nuclear structure information accessible today, in particular that of one of the most exotic neutron-rich nuclei currently accessible to experiment, 40Mg, which lies at the intersection of the nucleon magic number N=28 and the dripline, and is expected to have a large prolate deformation similar to that observed in the neighboring lighter isotopes 32-38Mg. In addition, the occupation of the weakly bound p3/2 state may lead to the appearance of an extended neutron halo. Thus 40Mg offers an exciting possibility and a rare opportunity to investigate the coupling of weakly bound valence particles to a deformed core, and the influence of near threshold effects on collective rotational motion. I will present the results of an experiment carried out at RIBF RIKEN to study low-lying states in 40Mg populated in a 1-proton removal reaction from a 41Al secondary beam. The observed excitation spectrum is shown to reveal unexpected properties as compared to both neighboring (more bound) Mg isotopes and theoretical model predictions. This work is supported by the U.S. Department of Energy, Office of Nuclear Physics, under contract no DE-AC02-05CH11231.
31 Oct

Conceptual design of the HRS

31 October 2019 - 11:00 AM
1200 FRIB Laboratory
Michigan State University

Shumpei Noji

04 Nov

Recent progress of IFMIF prototype accelerator and plan of A-FNS

04 November 2019 - 10:00 AM
1200 FRIB Laboratory
Rokkasho Fusion Institute

Atsushi Ksugai

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The development of Linear IFMIF Prototype Accelerator (LIPAc) is underway under the international collaboration between EU and Japan framed by the Broader Approach (BA) Agreement. QST (Japan) and F4E coordinating the European contributions of CEA Saclay (France), CIEMAT (Spain), INFN (Italy) and SCK-CEN (Belgium) are implementing the project. The LIPAc is a CW deuteron beam accelerator consisting of the injector (100 keV), Radio-Frequency Quadrupole linear accelerator (RFQ: from 100keV to 5MeV), Medium Energy Beam Transport (MEBT), Superconducting linear accelerator (SRF: from 5MeV to 9 MeV), Diagnostic-Plate, High Energy Beam Transport (HEBT) and High Power Beam Dump (HPBD). The RFQ was installed in 2016 and the first H+ beam was accelerated. The D+ operation was carried out, and the target value ( 125 mA at 5 MeV) was achieved on July, 2019 with the short pulse (1ms). A long pulse commissioning of the RFQ is planned in 2020 using the HPBD to validate the full RFQ design as well as all the other systems composing the line in long pulse especially the high energy part. The SRF linac is under assembly in the clean room at QST. The SRF consists of a horizontal cryostat of around 6 m long, 3 m high and 2 m wide, which includes 8 superconducting Half Wave Resonators for beam acceleration working at 175 MHz and at 4.5 K, 8 power couplers to provide RF power to cavities, and 8 solenoid packages as focusing elements. The SRF linac will be installed after the long pulse commissioning phase. On the other hands, Advanced Fusion Neutron Source A-FNS, which is planned by QST as Japanese fusion neutron source, the conceptual design is on going. We are to conduct neutron irradiation experiments for materials of DEMO fusion reactor, and also use the neutrons for application except for the fusion reactor. A-FNS is mainly composed of an accelerator, a liquid lithium target and a test facility. The accelerator for A-FNS is presently based on the design of LIPAc. The liquid lithium target is based on the test results by IFMIF/EVEDA liquid lithium test loop, and the basic specification is established. I will report the progress of the conceptual design of A-FNS.
05 Nov

Parity-violating neutron spin rotation in 4He

05 November 2019 - 11:00 AM
1200 FRIB Laboratory
Rare Isotope Science Project, Institute for Basic Science

Young-Ho Song

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The parity-violating neutron spin rotation in 4He is studied at vanishing incident neutron energy limit. Calculations have been realized by solving five-body Faddeev-Yakubovsky equations in configuration space employing modern strong-interaction Hamiltonian based on chiral perturbation theory including three-nucleon force. Parity-violating nucleon-nucleon interaction of the Desplanques, Donoghue, and Holstein model is employed. An implication of the recent theoretical large-Nc estimation of weak couplings [Phillips et al., Phys. Rev. Lett. 114, 062301 (2015)] is also discussed.
06 Nov

Recent extension of the neutron dripline at RIKEN and what to expect from FRIB

06 November 2019 - 4:10 PM
1200 FRIB Laboratory
Michigan State University

Oleg Tarasov

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A search for the heaviest isotopes of fluorine, neon and sodium was conducted by fragmentation of an intense 48Ca beam at 345 MeV/nucleon with a 20-mm thick beryllium target and identification of isotopes in the large-acceptance separator BigRIPS at RIKEN RIBF. No events were observed for 32,33F, 35,36Ne and 38Na and only one event for 39Na after extensive running [1]. Comparison with predicted yields excludes the existence of bound states of these unobserved isotopes with high confidence levels. The present work indicates that 31F and 34Ne are the heaviest bound isotopes of fluorine and neon, respectively. The neutron dripline has thus been experimentally confirmed up to neon for the first time since 24O was confirmed to be the dripline nucleus nearly 20 years ago [2,3]. These data provide new keys to understanding the nuclear stability at extremely neutron-rich conditions. Finally, the potential to determine drip-lines for light elements, and move close to drip-lines for higher elements at the Facility for Rare Isotope Beams / MSU [4,5] will be presented. Main requirements for qualitative prediction of production cross sections of unknown isotopes will be discussed. References: [1] Location of the neutron drip line at fluorine and neon, D. S. Ahn, N. Fukuda, H. Geissel, N. Inabe, N. Iwasa, T. Kubo, K. Kusaka, D. J. Morrissey, D. Murai, T. Nakamura, M. Ohtake, H. Otsu, H. Sato, B. M. Sherrill, Y. Shimizu, H. Suzuki, H. Takeda, O. B. Tarasov, H. Ueno, Y. Yanagisawa, and K. Yoshida, accepted for publication in Physical Review Letters. [2] D. Guillemaud-Mueller et al., Phys. Rev. C 41, 937 (1990). [3] O. B. Tarasov et al., Phys. Lett. B 409, 64 (1997). [4] T. Glasmacher, B. Sherrill, W. Nazarewicz, A. Gade, P. Mantica, J. Wei, G. Bollen, and B. Bull, Nucl. Phys. News 27, 28 (2017). [5] B. M. Sherrill, EPJ Web of Conferences 178, 01001 (2018).
07 Nov

New measurement of the 1S-3S transition frequency of hydrogen: Contribution to the proton charge radius puzzle

07 November 2019 - 11:00 AM
1200 FRIB Laboratory
Michigan State University

Skyy Pineda

08 Nov

The lanthanide fraction distribution in r-process metal-poor stars

08 November 2019 - 2:00 PM
2025 FRIB Laboratory
Carnegie Observatory

Alexander Ji

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Multimessenger observations of the neutron star merger GW170817 and its kilonova proved that neutron star mergers can synthesize large quantities of r-process elements. If neutron star mergers in fact dominate all r-process element production, then the distribution of kilonova ejecta compositions should match the distribution of r-process abundance patterns observed in stars. The lanthanide fraction (XLa) is a measurable quantity in both kilonovae and metal-poor stars, but it has not previously been explicitly calculated for stars. Here, we compute the lanthanide fraction distribution of metal-poor stars ([Fe/H] -2.5) to enable comparison to current and future kilonovae. The full distribution peaks at log XLa ~ -1.8, but r-process-enhanced stars ([Eu/Fe] > 0.7) have distinctly higher lanthanide fractions; log XLa > -1.5. We review observations of GW170817 and find general consensus that the total log XLa = -2.2 +/- 0.5, somewhat lower than the typical metal-poor star and inconsistent with the most highly r-enhanced stars. For neutron star mergers to remain viable as the dominant r-process site, future kilonova observations should be preferentially lanthanide-rich (including a population of ~10% with log XLa > -1.5). These high-XLa kilonovae may be fainter and more rapidly evolving than GW170817, posing a challenge for discovery and follow-up observations. Both optical and (mid-)infrared observations will be required to robustly constrain kilonova lanthanide fractions. If such high-XLa kilonovae are not found in the next few years, that likely implies that the stars with the highest r-process enhancements have a different origin for their r-process elements.
11 Nov

New approaches to astrophysical reactions with stable high-energy ion beams

11 November 2019 - 12:30 PM
1400 Biomedical and Physical Sciences Building
Goethe University Frankfurt

Rene Reifarth

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High energy beams of stable nuclei are mostly used as a first step to produce beams of radioactive species. However, there are interesting applications based on the direct usage of the accelerated stable nuclei. We recently performed an experiment at GSI using O-16 beam at an energy of 500 AMeV. We observed the Coulomb breakup into C-12 and He-4 after interaction with a thin lead target. The idea is to constrain the astrophysically very interesting C-12(a,g) rate, which is the time-reversed reaction of the investigated Coulomb breakup. Ion storage rings offer new opportunities to investigate astrophysically interesting reaction in inverse kinematics. We performed proton capture experiments on stable Xe-124 in the energy regime of the gamma-process. The xenon ions were first accelerated to about 100 AMeV then fully stripped, injected into the Experimental Storage Ring at GSI. The actual measurement was performed after the ions were slowed down to 5-10 AMeV using a hydrogen droplet target. Fully stripped ions can have a significantly shorter beta-decay half-life than neutral atoms. The corresponding process is called bound-state beta decay. In the extreme case, nuclei, which are stable under terrestrial conditions, can beta-decay in the inner-most regions of stars. This process can be investigated with ion storage rings. I will review recent accomplishments using stable high-energy beams to infer astrophysically interesting reaction rates. In addition, I will share and discuss ideas for future experiments.
13 Nov

Tentative thesis title: New machine learning algorithms for lattice QCD calculations

13 November 2019 - 12:00 PM
1108 FRIB Laboratory
NSCL Graduate Assistant

Giovanni Pederiva

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Committee: Andrea Shindler (Chairperson), Alexei Bazavov, Dean Lee, Carlo Piermarocchi, Jaideep Singh
15 Nov

MSU saxophone quartets concert

15 November 2019 - 5:30 PM
1300 FRIB Laboratory

MSU saxophone quartets concert

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This event is a chamber music concert featuring saxophone quartets (Backseat Quartet, Four, Group 2, and Sycamore) from the MSU Saxophone Studio. All of the students are pursuing undergraduate or graduate degrees in music performance and/or music performance, and are students studying with Professor Joseph Lulloff.
19 Nov

Uncertainty in the nuclear energy density functional: Going beyond the mean field

19 November 2019 - 11:00 AM
1200 FRIB Laboratory
Free University of Brussels

Erik Olsen

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Understanding astrophysical observables and phenomena requires a thorough knowledge of various properties of nuclei all over the nuclear chart. Since most of these systems are inaccessible through experiment, theoretical predictions are necessary. At present, nuclear Density Functional Theory is the only method available which can reach these systems while maintaining a microscopic character. Its key ingredient, the nuclear energy density functional, is an effective interaction based on one-body local densities and currents which contains a number of coupling constants whose values are optimized to experimental data and/or pseudo-data. Developing this interaction to minimize its root-mean-square error with respect to certain observables is crucial for more accurate astrophysical predictions. Past and current procedures in this endeavor will be discussed, as well as future plans to incorporate beyond-mean-field effects through both the cranking model and the generator coordinate method, as well as different approaches to the statistical fitting of the functional.
19 Nov

Investigation of the possibility of high efficiency L-Band SRF cavities for medium-beta heavy ion multi-charge-state beams

19 November 2019 - 2:30 PM
1200 FRIB Laboratory
Graduate Assistant

Safwan Shanab

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Committee: Kenji Saito(Chairperson), Morten Hjorth-Jensen, Chong-Yu Ruan, Jie Wei, Yoshishige Yamazaki. Thesis is on display in 1312 BPS Bldg. and NSCL Atrium
20 Nov

Short-range correlations and the quarks within

20 November 2019 - 4:10 PM
1200 FRIB Laboratory
Massachusetts Institute of Technology

Or Hen

Show/Hide Abstract
Short-range correlations (SRC) are pairs of strongly interacting nucleons at close proximity. Due to their large spatial overlap and high relative-momentum, the study of SRC pairs is an appealing gateway for probing the strong nuclear interaction at high-densities (i.e. short-distances) and its relation to the underlaying quark-gluon substructure of nuclei. In this talk I will present new results from high-energy electron scattering experiments that probe SRC pairs via measurements of exclusive hard breakup reactions. Special emphasis will be given to the effect of SRCs on the behavior of protons in neutron-rich nuclear systems and how it can impact properties of dense nuclear systems such as neutron stars. Pursuing a more fundamental understanding of short-distance interactions, I will present new measurements of the internal quark-gluon sub-structure of nucleons and show how its modification in the nuclear medium relates to SRC pairs and short-ranged nuclear interactions. Last, I will also discuss the development of new effective theories for describing short-ranged correlations, the way in which they relate to experimental observables, and the emerging universality of short-distance and high-momentum physics in nuclear systems.
21 Nov

Highlight in progress: Deep learning and the nuclear many-body problem

21 November 2019 - 11:00 AM
1200 FRIB Laboratory
Michigan State University

Julie Butler

21 Nov

Particle Accelerators at Los Alamos National Laboratory

21 November 2019 - 2:00 PM
1200 FRIB Laboratory
LANL

Stephen Milton

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The use of particle accelerators has a long history at Los Alamos National Laboratory (LANL), from their early use in radiography to their present day use in stockpile stewardship. There are two primary accelerator system in use today at LANL, LANSCE (the Los Alamos Neutron Science Center) and DARHT (the Dual-Axis Radiographic Hydrodynamic Test facility), and they are heavily subscribed. Recently, LANL formulated an overall laboratory accelerator strategy, and this strategy highlights both the need to maintain our current capabilities, but to also expand these capabilities to meet the ever evolving mission need. Following a summary of the history of accelerators at LANL, current systems and uses will be described. This will be followed with our vision of the future for accelerator systems at LANL.
23 Nov

So many elements, so little time

23 November 2019 - 10:30 AM
1300 FRIB Laboratory

Gregory Severin

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The radiation from rare isotopes allows us to detect them, but it also marks their decay. Radiochemists are constantly racing against the clock to utilize the traceability of radionuclides to improve our understanding of chemistry, medicine, physiology, nuclear physics, and many other interesting subjects. Sometimes too-short or too-long half-lives make that job difficult, and require us to mix and match elements outside of their natural environments. The plus side of that rearrangement is that radiochemists get to work with elements all across the periodic table. Who else plays with manganese, lanthanum, zirconium, thulium, and erbium all in the same week? Come see how fast and slow decays are used to trace all types of interesting processes with the most unlikely combination of elements.
25 Nov

JINA-CEE Science Cafe (link is external)

25 November 2019 - 2:00 PM
1400 Biomedical and Physical Sciences Building
MSU Physics and Astronomy

Sam Giuliani (Physics and Astronomy) and Luke Roberts (NSCL)

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"Signatures of nuclei beyond lead in kilonova light curves" and "Kilonovae: Basic properties and observations", respectively
02 Dec

r-process nucleosynthesis studies meet the next generation of observation and experiment

02 December 2019 - 11:00 AM
1200 FRIB Laboratory
University of Notre Dame

Nicole Vassh

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The astrophysical site(s) for the rapid neutron capture process which synthesizes the heaviest elements observed in nature has been a long outstanding question. The era of multi-messanger astronomy now permits unprecedented insights into astrophysical events, as evidenced by LIGO/VIRGO's ability to direct the telescope community to perform detailed electromagnetic follow-up for merger events such as GW170817. Nuclear physics experiment is simultaneously undergoing its own era of revolution by beginning to probe the very neutron-rich regions populated at crucial times during the r process, as is being done by the CPT at CARIBU. The next generation of nuclear physics experiment will push the boundary of explored nuclei even further. FRIB will produce hundreds of neutron-rich species for the first time, making them accessible for numerous studies which determine properties such as masses or beta-decay half-lives. But what exactly do these revolutions in experiment and observation mean for our understanding of the origin of the heaviest elements in our galaxy? The r-process nucleosynthesis studies I will present explicitly connect these avenues of exploration via considering how nuclear data influences r-process observational signatures. We will discuss the current uncertainties affecting r-process calculations and how these will be reduced by next generation experiments. Since the electromagnetic signal from merger events is highly influenced by the presence of high opacity lanthanide elements, we will focus our discussion on a feature of enhanced lanthanide production, the r-process rare-earth abundance peak, which could be intimately linked to the nuclear structure and deformation of neutron-rich lanthanide species. The alternative means by which the rare-earth peak can be produced is via late-time fission deposition which we will also examine in the context of new theoretical fission yields for neutron-rich nuclei. The question of where nature primarily produces the heavy elements can only be answered through such collaborative efforts between theory, experiment, and observation.
03 Dec

Applications of chiral forces up to N3LO
to finite nuclei and neutron stars

03 December 2019 - 11:00 AM
1200 FRIB Laboratory
University of California, Berkeley

Christian Drischler

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The exciting physics of neutron-rich matter covers a wide range of densities, from finite nuclei to neutron stars. Constraining the neutron-rich matter equation of state (EOS) simultaneously from experiment, observation, and theory is a very active field of research. In anticipation of novel constraints, e.g., from FRIB and multi-messenger astronomy, it is time to take advantage of the recent advances in chiral effective field theory (EFT) and many-body frameworks to improve microscopic predictions of the EOS based on chiral nuclear interactions. I will discuss several applications of a novel Monte Carlo framework for many-body perturbation theory to infinite nuclear matter with chiral two-, three-, and four-nucleon interactions. The efficiency of this framework allows for the incorporation of all many-body contributions up to high orders as well as the Bayesian estimation of theoretical uncertainties through order-by-order calculations. I will show results for the EOS of neutron and symmetric matter, the nuclear saturation point, the symmetry energy as well as its slope parameter, and a comparison to results based on quark-gluon degrees of freedom at intermediate densities. Nuclear matter is furthermore an ideal testbed for the development of chiral interactions aimed at precise nuclear structure and reaction calculations with quantifiable uncertainties across a wide range of the nuclear chart. As a first step, we fit chiral interactions up to next-to-next-to-next-to-leading order (N3LO) to the triton as well as the empirical saturation point. Such approaches have recently gained much attention since ab initio calculations of medium-mass to heavy nuclei have demonstrated that realistic saturation properties of chiral forces in infinite matter are important for reproducing experimental ground-state energies and charge radii. I will review our subsequent study of closed-shell medium-mass nuclei up to nickel using the ab initio In-Medium Similarity Renormalization Group (IM-SRG) and my conclusions for making progress in this direction.
03 Dec

Monte-Carlo Simulations of the (d,2He)reaction in the inverse kinematics

03 December 2019 - 5:10 PM
126 Chemistry Building
NSCL Graduate Assistant

Alexander Carls

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Committee: Remco G. Zegers(Chairperson), Sean Liddick, Wolfgang Mittig
04 Dec

Toward the drip lines with unified approaches to nuclear structure and reactions

04 December 2019 - 11:00 AM
1200 FRIB Laboratory
Louisiana State University

Alexis Mercenne

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The upcoming experiments at the Facility for Rare Isotope Beams will unlock unique opportunities to probe an uncharted territory near the drip lines, posing new challenges to nuclear theory. My research program plans to address some of these challenges, with the goal to provide reliable descriptions of exotic systems that exhibit low-lying unbound states and are often spatially expanded. To achieve this, I will develop a novel unified approach to nuclear structure and reactions, coupled with high performance computing, that merges collectivity and the continuum, the two most important degrees of freedom for unstable nuclei. This will be built upon my recent developments that have opened the medium-mass region of nuclei, deformed or not, for studies of reactions from first principles, using a physically relevant symmetry-based basis. It will also build on my recent generalization of a shell-model approach to heavier projectiles that utilizes a scattering-relevant (Berggren) basis and the coupling to the continuum. To highlight some examples, I will talk about the first ab initio calculations of the proton scattering phase shift on 20Ne based on the symmetry-adapted no-core shell model, as well as Gamow shell model studies of d-_ and of the 15F unbound system through the proton scattering reaction on 14O. These new advances will contribute to the exploration of the neutron drip line, especially through (n, ) or (d,p) reactions, first for light and medium-mass nuclei, but eventually expanded to heavy nuclei in the r-process through the construction of ab initio and microscopically informed optical potentials. This, in turn, will provide unprecedented tools that will help further our understanding of the physics beyond the valley of stability, the physics of neutrons, and various astrophysics processes.
04 Dec

Nuclear structure and dynamics from ab initio theory

04 December 2019 - 4:10 PM
1200 FRIB Laboratory
TRIUMF

Petr Navratil

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A realistic description of atomic nuclei, in particular light nuclei characterized by clustering and low-lying breakup thresholds, requires a proper treatment of continuum effects. We have developed an approach, the No-Core Shell Model with Continuum (NCSMC) [1,2], capable of describing both bound and unbound states in light nuclei in a unified way. With chiral two- and three-nucleon interactions as the only input, we are able to predict structure and dynamics of light nuclei and, by comparing to available experimental data, test the quality of chiral nuclear forces. I will discuss applications of NCSMC to weakly bound halo nuclei and nuclear reactions important for astrophysics such as 8Li(n,

γ

)9Li, 11C(p,

γ

)12N and 14C(n,

γ

)15C radiative captures. I highlight our calculations of polarization effects in the 3H(d,n)4He fusion and its mirror reaction 3He(d,p)4He [3]. These transfer reactions are relevant for primordial nucleosynthesis and 3H(d,n)4He in particular is being explored in large-scale experiments such as NIF and ITER as a possible future energy source. I will also discuss our contributions to the development of chiral three-nucleon interactions and calculations of matrix elements relevant for beta decay and neutrinoless double beta decay studies. Supported by the NSERC Grant No. SAPIN-2016-00033. TRIUMF receives federal funding via a contribution agreement with the National Research Council of Canada.
05 Dec

Study of the eikonal approximation to model exotic reactions

05 December 2019 - 11:00 AM
1200 FRIB Laboratory
Universite libre de Bruxelles

Chloe Hebborn

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In the mid-eighties, the development of radioactive-ion beams has enabled the study of nuclei far from stability. This technical breakthrough has led to the discovery of nuclei which display unexpected structures, challenging the usual description of nuclear matter. In particular, in the neutron-rich region, halo nuclei have been observed. These nuclei exhibit a very large matter radius compared to their isobars. Since they are short-lived, they cannot be studied through the usual spectroscopic techniques but they are mostly probed with reactions, such as elastic scattering, breakup and knockout. To extract precise information from these measurements, an accurate reaction model coupled to a realistic description of the nucleus is needed. The eikonal model is reliable at high energies, i.e., above 60 MeV/nucleon, and has a short computational time. During this seminar, I will present three different projects on the eikonal model that I have conducted during my PhD. My first project is the extension of the eikonal model to lower energies, i.e., 10 MeV/nucleon, in the energy range of the new facilities ReA12 at FRIB and HIE-ISOLDE at CERN. To improve the eikonal model at low energies, I have studied corrections to the nuclear deflection of the projectile by the target. I have assessed their efficiency for the elastic scattering and breakup of one-neutron halo nuclei. My second research topic is the development of an eikonal-like model which treats at the first-order the dynamics of the projectile during the collision. This new model has a similar numerical cost as the eikonal model but does not diverge for the Coulomb breakup, since it corrects for the adiabatic approximation. My third research is on knockout reactions and which nuclear structure information can be inferred from such measurements. To identify what can be probed with such reactions, I have used a halo effective-field theory to describe the projectile. Finally, I will present my research plans for the FRIB-Theory Fellowship. My idea is to bridge reaction theory with ab initio theory through the development of optical potentials from the no-core shell model with continuum calculations.
05 Dec

Accelerator and beam physics research opportunities at Fermilab

05 December 2019 - 2:00 PM
1200 FRIB Laboratory
FNAL

Vladimir Shiltsev

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Fermilab is the US leading accelerator laboratory with an illustrious history in design, construction and operation frontier accelerators for particle physics research. I will briefly present current status of Fermilab accelerators and our plans for the next decade and will discuss in length accelerator and beam physics research opportunities at Fermilab, including IOTA and FAST experiments, topics related to the Fermilab complex upgrades, beam theory/modeling and simulations, development of new SRF cavities and systems, high field SC magnets and advanced superconducting materials.
06 Dec

Nuclear reactions from a three body perspective

06 December 2019 - 11:00 AM
1200 FRIB Laboratory
Istituto Nazionale di Fisica Nucleare, Sezione di Pisa

Jin Lei

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Nuclear reactions generate energy in nuclear reactors, in stars, responsible for the existence of all elements heavier than Hydrogen in the universe and provide information of nuclear structure. An important mechanism that takes place in the nuclear collisions is the dissociation of the projectile into two or more fragments. For the two-body dissociation, this corresponds to reactions of the form a(=b + x) + A -> b + x +A. The theoretical interpretation of these reactions is studied by Faddeev and later reformulated by Alt-Grassberger- Sandhas (AGS) in momentum space. In this talk, I will discuss about solving the Faddeev-AGS equation with separable form interactions which have the advantages to include the Coulomb interaction exactly. In addition, I will also discuss about the inclusive breakup, which takes the form a+A-> b + anything, and several applications based on the studies of inclusive breakup.
06 Dec

N=7 shell evolution at and beyond the neutron dripline

06 December 2019 - 12:00 PM
1200 FRIB Laboratory
Graduate Research Assistant

Daniel Votaw

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Committee: Michael Thoennessen(chairperson), Daniel Bazin, Scott Bogner, Laura Chomiuk, Wade Fisher
09 Dec

Classical novae as lithium factories in the galaxy

09 December 2019 - 12:30 PM
1400 Biomedical and Physical Sciences Building
DARK/NBI, University of Copenaghen

Luca Izzo

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The abundance of lithium observed in very young stellar populations is few times larger than the primordial one estimated by recent Planck measurements. Since Lithium is easily destroyed in the stellar interiors, the search for astrophysical sources responsible for the observed lithium over-abundance was a challenge for decades. In this talk I will present the results of an on-going survey dedicated to the study of nova outburst with high-resolution spectrographs at ESO/VLT. In particular, I will concentrate on the recent detection of beryllium-7 in the spectra of recent classical novae. While this finding is a further confirmation of the occurrence of the thermo-nuclear runaway in nova explosions, at same time it implies that classical novae are one of the main factories of lithium in our Galaxy (and other nearby systems).
12 Dec

Development of a single-atom microscope for optical detection of atomic nuclear reaction products

12 December 2019 - 1:00 PM
1200 FRIB Laboratory
NSCL Graduate Assistant

Benjamin Loseth

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Committee: Jaideep Singh(Chairperson), Luke Roberts, Hendrik Schatz, Stuart Tessmer, Kirsten Tollefson. Thesis is on display in 1312 BPS bldg. and the NSCL atrium.
14 Dec

Life under blazing stars: supernova mysteries

14 December 2019 - 10:30 AM
1300 FRIB Laboratory

Georgios Perdikakis

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The atoms that make up the world we live in have affected human life for thousands of years. All of the prosperity, peace, culture, power, and progress we experience is based on the availability of the planet's natural resources. We value the rarest of elements we can find on Earth. We use them in technology, art, and jewelry. We need these elements to sustain our living bodies. As resources run out, we turn to quests for new habitable worlds to mine. Yet, meaningful pieces of information about the origin of elements in the universe are lost to us. Scientists have turned to the stars and to the atomic nucleus to understand supernovae and other spectacular explosions. To uncover how the fateful pattern of element compositions came to be in our corner of the universe (or elsewhere), we will need to understand thousands of nuclear reactions in stars and predict their outcome. Most of these reactions with the mysterious isotopes that live and die inside blazing stars have not been observed yet. But with a facility in East Lansing that will make supernova isotopes into beams, it's only a matter of time before new discoveries will be made.

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