Facility for Rare Isotope Beams

V.S. Morozov¹, R. Suleiman², and Ya.S. Derbenev² present a new design of highly specialized small storage rings for low-energy polarized electron beams. The new design is based on the transparent spin methodology that cancels the spin precession due to the magnetic dipole moment at any energy while allowing for spin precession induced by the fundamental physics of interest to accumulate. The buildup of the vertical component of beam polarization can be measured using standard Mott polarimetry that is optimal at low electron energy. These rings can be used to measure the permanent electric dipole moment of the electron, relevant to CP violation and matter-antimatter asymmetry in the universe, and to search for dark energy and ultra-light dark matter. ¹Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA. ²Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA.

My research group focus on applying molecular ions on a variety of scientific applications such as quantum information processing, study of cold chemistry, and searches for new physics beyond the Standard Model. In this talk, I will present two ongoing electrons electric dipole moment (eEDM) experiments. One is trapping thousands of HfF+ or ThF+ ions in a large Paul trap in a rotating frame that aims for high signal throughput and moderately long coherence time. The other is applying quantum logic protocol to precisely control and detect a single ion (ThF+ or TaO+) in a cryogenic surface ion trap that targets for extremely long coherence, low systematics, and parallelism. Furthermore, extensions of the similar measurements to other new physics exploration, such as measuring nuclear magnetic quadrupole moment (NMQM) and searching for axion dark matter, will be discussed as well.

Committee: Remco Zegers (Chairperson), B. Alex Brown, Wolfgang Kerzendorf, Artemis Spyrou, Nathan Whitehorn

I will present how the properties of the first stars can be derived from the abundance patterns of extremely metal-poor (EMP) stars in the Milky Way. After a general introduction and motivation, I will present our recent research results: based on theoretical models of the chemical yields of the first supernovae, we train Support Vector Machines to classify EMP stars. This AI-based approach predicts if a specific abundance pattern is consistent with supernova enrichment by one or by several progenitor stars (mono- or multi-enriched). By applying the trained classifier to actual observations, we find that most EMP stars are multi-enriched, which is the first observational confirmation for the multiplicity of the first stars.

Committee: Morten Hjorth-Jensen (Chairperson), Scott Bogner, Marcos Caballero, Kaitlin Cook, Johannes Pollanen

Committee: Alexandra Gade (Chairperson), B. Alex Brown, Wade Fisher, Claudio Kopper, Sean Liddick

Committee: Witek Nazarewicz (Chairperson), Alexei Bazavov, Scott Bogner, Ekaterina Rapinchuk, Hendrik Schatz

We discuss a nonrelativistic version of Georgis "unparticle physics". An "unnucleus" is a field in a nonrelativistic conformal field theory characterized by a mass and a scaling dimension. It is realized approximately in high-energy nuclear reactions involving emission of a few neutrons with relative energies between about 0.1 MeV and 5 MeV. Conformal symmetry predicts a universal power law behavior of the inclusive cross section in this kinematic regime and relates it to the energy levels of fermions in a harmonic trap. Certain bosonic systems may also show unnucleus behavior. We argue that it may be possible to create unnuclei of neutral D mesons in short-distance reactions at the LHC.

High voltage DC photoemission electron guns have demonstrated high performance for a variety of meaningful accelerator applications; a) ultra-high vacuum required for obtaining long-photocathode lifetime from high polarization GaAs photocathodes for nuclear physics, b) generating tens of mA for electron coolers, energy recovery linacs, and free-electron lasers, and c) bright electron beams for electron microscopy and for ultra-fast electron diffraction. The photocathode accelerating field must be sufficiently high (often > 10 MV/m) to compensate for high bunch charge and improve injector transmission, imposing challenging requirements to reliably apply high voltage to the electrodes and HV feedthroughs without breakdown. Further, the electrodes must be free of field emission to preserve the vacuum conditions necessary for long photocathode lifetime. At Jefferson Lab, we have developed compact DC high voltage photoguns based on an inverted-geometry ceramic insulator concept. Our design is based on achieving exceptional vacuum, being free of field emission and operating with reliable approaches to applying high voltage to the photogun. I will provide an overview of DC photogun designs in operational accelerators, practical considerations to reliably apply high voltage, and summarize both successes and failures learned over the two past decades in building these photoguns.

Neutron resonance transmission analysis technique (NRTA) uses resonance phenomenon to identify the isotopic composition of unknown materials. Several mid-Z to high-Z elements have discrete energy levels 1 eV- 100 eV above the neutron separation energy. In this energy range, the transmission spectra of epithermal neutrons for these elements exhibit unique resonant signatures due to which NRTA has found its applications in the field of archaeology, warhead verification and spent fuel analysis. Presence and quantification of special nuclear materials such as U-235, U-238, Pu-239 and Pu-240 with NRTA is being explored, however its application is currently limited due to the availability of calibrated, strong neutron sources only at large experimental facilities. To eliminate this limitation, we have studied the feasibility of doing NRTA with a mobile, small-scale setup using a commercially available deuterium-tritium (DT) neutron source manufactured by Thermo Fisher Inc. Time-of-flight is measured to provide the energy of the transmitted epithermal neutrons. Experimental measurements were performed for a variety of targets and the results on resolution in the transmitted energy spectrum demonstrate the capability of performing isotopic analysis using a compact and simple setup.

Committee: B. Alex Brown (Chairperson), Alexei Bazavov, Alexandra Gade, Dean Lee, Scott Pratt, Yang Yang

Nuclear astrophysics is generally the study of the energy generation in stars and the origins of the chemical elements. In this highly multidisciplinary field, the job of experimental nuclear physicists is to constrain the nuclear reaction rates which are linked with astronomical observables. Observation of the lightest chemical element with no stable isotopes, technetium, in stellar spectra, was the first evidence that nucleosynthesis is an on-going process in our Galaxy. While the Big Bang is the generally accepted origin of the Universe, the observed results of cosmological lithium from these thirty minutes of nucleosynthesis in the early, hot, dense Universe, remain discrepant with nuclear physics data by a factor of three. Observation of solar neutrinos and those from supernova 1987A gave further evidence for on-going nucleosynthesis, although understanding the precise quantity of solar neutrinos required several decades of research to resolve another mysterious factor of three. Meanwhile, a radioisotope of aluminium, with a half-life of under one million years, was observed to be co-rotating with the Galaxy by its Doppler shift. Most recently, the observation of a binary neutron star merger in both gravitational and electromagnetic waves provided the first direct observational evidence for a site of the rapid neutron capture process. These and other simple examples which both give strong evidence to the theory of nucleosynthesis as well as future challenges will be discussed, in particular from an experimental point of view.

RIKEN RI Beam Factory (RIBF) began operating in 2007, and since then, about 200 experiments were performed with high-intensity RI beams. BigRIPS is a core experimental device in RIBF, which is a superconducting RI-beam separator to produce and supply a wide range of RI beams in the nuclear chart. The RI beams have been produced from 345-MeV/u 238U or other stable heavy-ion beams supplied from the accelerator complex by in-flight fission or projectile fragmentation. 100-1000 times higher-intensity RI beams can be supplied at RIBF, compared to other facilities in the world, leading to the discovery of 152 new isotopes in these 14 years.

The Compton Spectrometer and Imager (COSI) is a Small Explorer (SMEX) satellite mission selected by NASA for development and scheduled for launch in late-2025. COSI is a wide-field telescope designed to survey the entire gamma-ray sky at 0.2-5 MeV. It provides imaging, spectroscopy, and polarimetry of astrophysical sources, and its germanium detectors provide excellent energy resolution for studies of nuclear lines. Science goals for COSI include mapping radioactive elements (Al26, Fe60, Ti44) from nucleosynthesis, studies of 511 keV emission from antimatter annihilation in the Galaxy, determining emission mechanisms and source geometries with polarization, and detecting and localizing multimessenger sources. In addition, COSI's all-sky MeV survey with improved sensitivity over previous missions explores new discovery space. In this talk, I will describe the COSI instrument design, how its operation has been verified via high-altitude balloon flights, and the science that the COSI satellite mission will enable.

Neutron stars (NSs) allow us to probe fundamental interactions at densities otherwise inaccessible in the lab, up to as much as ~6 times nuclear saturation density. By using multi-messenger astrophysical observations of NSs, we can constrain the Equation of State (EoS) of dense matter and better determine how astrophysical objects may behave in a variety of environments. I will review the basic principles behind recent observations of coalescing compact binaries containing NSs with Gravitational Waves as well as both radio and X-ray observations of pulsars. Using these observations, I'll show how we can learn about both the microphysical properties of nuclear interactions and correlations with their macroscopic properties at the same time. In particular, I will show tantalizing hints at the possibility of phase transitions within NS cores, our ability to determine when nuclear theoretic calculations break down, and implications for the radii and masses NSs may achieve. Throughout, I'll highlight how modeling assumptions can (strongly) affect our conclusions and advocate for transparency within such analyses, including which data is selected for analysis.

Committee: Man-Yee B. Tsang (Chairperson), Edward Brown, Pawel Danielewicz, Tyce DeYoung, William Lynch. Thesis is available at https://pa.msu.edu/academics/graduate-program/current-graduate-students/draft-dissertations-for-review/ - Select student name

The strong suppression of bottomonia in ultrarelativistic heavy-ion collisions is a smoking gun for the production of a deconfined quark-gluon plasma (QGP). In this talk I will discuss recent work that aims to provide a more comprehensive and systematic understanding of bottomonium dynamics in the QGP. The new paradigm is based on an open quantum system approach applied in the framework of potential-based non-relativistic QCD (pNRQCD). I demonstrate that the computation of bottomonium suppression can be reduced to solving a Lindblad-type equation for the evolution of the b-bbar density matrix including both singlet and octet states and transitions between them. To solve the resulting Lindblad equation, we make use of a quantum trajectories algorithm which can be deployed in a massively parallel manner. Our computation depends on two transport coefficients that have been evaluated independently using lattice QCD. Our final phenomenological predictions are found to agree quite well with available data from LHC 5.02 TeV Pb-Pb collisions for both bottomonium suppression and elliptic flow. References: 1. Bottomonium production in heavy-ion collisions using quantum trajectories: Differential observables and momentum anisotropy, https://arxiv.org/abs/2107.06222 2. QTRAJ 1.0: A Lindblad equation solver for heavy-quarkonium dynamics, https://arxiv.org/abs/2107.06147

The Electron-Ion Collider (EIC) is being designed for construction at Brookhaven National Laboratory (BNL), as a joint DOE effort between Jefferson Lab (JLab) and BNL. CD-1 status was awarded in the middle of 2021, and technical design efforts are underway to concentrate on readiness for CD-2. The speaker will present a current overview of the collider design and R&D, with an emphasis on accelerator physics and technology challenges.

Beam diagnostics for resolving internal structure of a bean in an accelerator use interaction of the beam particles with a probe that can be inserted in the beam. Many types of probes can be used for this purpose, from a simple wire to a beam of different particles. Negative ions of hydrogen (H-) are widely used in initial stages of high intensity circular proton acceleration. These particles interact efficiently with photons; therefore, a laser beam makes an ideal probe for diagnostics of H- beams. Lasers can be used to measure many important beam parameters: transverse and longitudinal beam size, transverse and longitudinal emittances, beam energy and intensity. A review of the laser-based beam diagnostics will be given in this talk. Most of the material is based on the experience from the Spallation Neutron Source, the world highest power H- accelerator

The ordinary atoms that make up the known universe, from our bodies and the air we breathe to the planets and stars, constitute only 5 percent of all matter and energy in the cosmos. The remaining 95 percent is made up of a recipe of 25-percent dark matter and 70-percent dark energy, both nonluminous components whose nature remains a mystery. Katherine Freese will recount the stories of the dark matter puzzle, starting with the discoveries of visionary scientists from the 1930s who first proposed its existence, to Vera Rubin in the 1970s whose observations conclusively showed its dominance in galaxies, to the deluge of data today from underground laboratories, satellites in space, and the Large Hadron Collider. Theorists contend that dark matter most likely consists of new fundamental particles; the best candidates include weakly interacting massive particles (WIMPs) and axions. Billions of them pass through our bodies every second without us even realizing it, yet their gravitational pull is capable of whirling stars and gas at breakneck speeds around the centers of galaxies, and bending light from distant bright objects. This talk will overview this cosmic cocktail, including the evidence for the existence of dark matter in galaxies. Many cosmologists believe we are on the verge of solving this mystery and this talk will provide the foundation needed to fully fathom this epochal moment in humankind's quest to understand the universe.

Committee: Peter Ostroumov (Chairperson), Yue Hao Steven Lidia, Michael Murillo, Scott Pratt

Atom Trap Trace Analysis (ATTA) is a highly selective and sensitive atom counting technique based on laser cooling and trapping. It has now been established as a routine tool in the geosciences for radiokrypton dating of ancient groundwater and glacial ice samples on timescales of a few ten thousands to a couple million years. The isotope of interest here is the cosmogenic krypton-81 with its half-life of 230 thousand years and its isotopic abundance at the parts-per-trillion level in the atmosphere. While the development of ATTA into a routine and reliable technique has already stretched over two decades, there is still large room for improvements in its sensitivity, precision, and sample throughput. In this talk, I will introduce the basic principles of ATTA, highlight some of its recent advances, and cover its future potential. I will also present some recent examples of radiokrypton analysis of ancient groundwater and their impact on understanding groundwater resources and paleoclimatic changes – including a puzzling discovery of underground production of krypton-81 found in water sample from a deep mine in South Africa.

Radiative capture reactions involving the fusion of hydrogen or helium are of critical importance in a wide range of astrophysical burning and explosion scenarios, such as main sequence and red giant stars, classical novae, supernovae or type I X-ray bursts, where these reactions govern the nucleosynthesis and energy generation. However, at typical peak temperatures for static and explosive stellar scenarios, the radiative capture reaction cross sections become vanishingly small, and thus extremely challenging to study experimentally. To overcome these challenges, the DRAGON (Detector of Recoils And Gammas Of Nuclear Reactions) recoil spectrometer at the TRIUMF-ISAC Radioactive Ion Beam Facility has been designed to directly measure radiative capture reactions of importance for nuclear astrophysics in inverse kinematics. To date DRAGON still holds the record for the number of direct measurements of radiative capture reactions performed with radioactive ion beams world-wide. Recoils emerging from the differentially pumped windowless gas target in a range of charge states are separated from the un-reacted beam in the 21 m long electromagnetic mass separator and detected in a DSSSD or ionization chamber. The inverse kinematics approach allows for measurements of reactions on very short-lived radioactive nuclei while the recoil separator provides high background suppression of 10 to 12 order of magnitude. Gammas from the de-excitation of the compound nucleus are detected in the high-efficiency BGO detector array surrounding the target. This provides an additional means of reaction identification and further increases the background suppression and sensitivity. I will give an overview of specifications and operation of the DRAGON recoil separator for performing direct measurements of radiative capture reactions at TRIUMF, before presenting examples of recent experimental highlights demonstrating DRAGON’s unique capabilities.

As reaction plane direction in heavy-ion collisions can be determined only coarsely, any attempt to measure 3D differential distributions, including over azimuthal angle, will yield blurred results. Deblurring procedures, analogous to those in optics, are proposed to correct for the coarse reaction-plane procedures and, simultaneously, any instrumental inefficiencies, to arrive at 3D distributions tied to the true reaction plane. The refined 3D picture of the collisions can yield better access to the physics than the current method of azimuthal moments. The deblurring procedures are likely to be effective in other cases where signals in nuclear measurements are degraded by instrument performance or methodology.

Understanding the dynamics of hadrons with strangeness has received a lot attention over the past decades in connection with the study of exotic atoms, the analysis of strangeness production and propagation in particle and nuclear research facilities, and the investigation of the possible strange phases in the interior of neutron stars. One venue of interest in the field of strangeness is the study of strange baryons, the so-called hyperons, and their dynamics with nucleons and nuclear matter. Theoretical studies have gone hand in hand with scattering experiments employing secondary hyperon beams or, more recently, using femtoscopy techniques. Also, the possible formation of nuclei with one or more hyperons inside the nucleus, the so-called hypernuclei, has triggered a lot of theoretical advances. Moreover, understanding the behaviour of hyperons in the presence of a surrounding dense medium is of particular interest to determine the features of the possible phases of dense matter in compact astrophysical objects, such as neutron stars. In this talk I will review the dynamics of hyperons with nucleons and nuclear matter. I will also discuss the presence of hyperons in the inner core of neutron stars and the consequences for the structure of these compact stars.

Three-nucleon force and continuum play important roles in reproducing the properties of atomic nuclei around driplines. Therefore it is valuable to build up a theoretical framework where both effects can be taken into account. One elegant choice is expressing the chiral three-nucleon force within the continuum Berggren representation so that bound, resonant, and continuum states can be treated on an equal footing. In this talk, I will first present the details of this framework. To uncover their effects, two particular cases will be discussed: 1) neutron-rich oxygen isotopes; 2) proton-rich Borromean Neon-17. The calculation shows that 3NF and continuum will play crucial but different roles in these threshold-nearing systems. As a separate topic, I would also like to introduce some ongoing progress on finite temperature neutron matter calculations within the framework of NLEFT

A narrow near-threshold proton-emitting resonance (Ex = 11.4 MeV, J π = 1/2+ and Îp = 4.4 keV) was directly observed in 11B via proton resonance scattering. This resonance was previously observed in the β-delayed proton emission of the neutron halo nucleus 11Be [1]. The good agreement between both experimental results serves as a ground to confirm the existence of such exotic decay and the particular behavior of weakly bound nuclei as open quantum systems. R-matrix analysis and single-particle resonance show in agreement with the data that the resonance effect reaches far beyond the resonance width due to the fast increase of penetrability in this below-barrier domain. This unusual behavior can be considered as paradigm of an open quantum system. The shape of the resonance, a consequence of the interplay between the reaction mechanism and structure, clearly reveals the open quantum system nature of such narrow resonances. The resonance properties will be discussed with respect to the spectroscopic factor as obtained from R-matrix analysis.

Accelerators ranging from midscale RF photoinjectors for femtosecond electron-diffraction experiments, to kilometer long free electron lasers that produce femtosecond x-ray pulses are utilized to resolve materials with atomic precision on femtosecond timescales. While the performance and recent results of these facilities are extraordinary, ensuring their continued vitality requires us to explore new accelerator physics and innovate the next generation of technology. One approach to achieving performance and accelerating gradients orders of magnitude above present capabilities is to dramatically increase the operational frequency into the Terahertz (THz) range. We are exploring accelerating structures designed to withstand high gradients and able to manipulate high-charge beams on femtosecond timescales; developing novel electronic and photonic THz sources; and laying the foundation for THz accelerator technology. Results from recent experiments on high gradient THz accelerators and their application to time stamping and electron bunch compression for ultrafast electron diffraction will be presented, along with a future outlook for the field.

In 2020, The American Institute of Physics released its groundbreaking TEAM-UP Report, The Time is Now: Systemic Changes to Increase African Americans with Bachelors Degrees in Physics and Astronomy following a rigorous research study by the TEAM-UP Task Force to understand the reasons for the persistent underrepresentation of African American students earning bachelors degrees in these fields. In this talk, Ms. Knowles will present findings from this study; discuss efforts to implement the reports recommendations among a select group of physics and astronomy departments committed to systemic change; share some strategies for supporting students; and reveal the next exciting steps for the TEAM-UP project.

Binary neutron star mergers provide a unique probe of the dense-matter equation of state (EOS) across a wide range of parameter space, from the cold EOS during the inspiral to the finite-temperature EOS following the merger. In this talk, I will start with an overview of what we have learned about the EOS from the first few LIGO-Virgo observations of binary neutron star inspirals. I will then discuss what additional EOS information can be extracted by studying the late-stages of a binary neutron star merger, during which time the matter is heated to significant temperatures and can deviate away from its initial equilibrium composition. I will present a new set of neutron star merger simulations, which use a parametrized framework for calculating the EOS at arbitrary temperatures and compositions. I will show how varying the properties of the particle effective mass affects the thermal profile of the post-merger remnant and how this, in turn, and influences the post-merger evolution. I will discuss the imprint of the nuclear symmetry energy on the post-merger properties. Finally, I will provide a new set of quasi-universal relations that can be used to constrain the dense-matter EOS with future gravitational wave events.

People face challenges in imagining scales very different from their own experiences. Scientists have systematically tackled some of those challenges through measurements and theoretical frameworks in which to interpret them. Professor Randall will discuss how the theme of organizing according to the size of the system plays a critical role in scientific research. This includes examples from her own research on particle physics, extra dimensions of space, and cosmology. She will also explore advances in human thought more generally, and the utility of parceling concepts according to this organizing principle.

The effort to understand the properties of nuclear matter has led to the construction of large and elaborate experimental facilities (like FRIB!). To maximize the scientific knowledge gained from the data, the theoretical models needed to explain and predict nuclear dynamics also grow in complexity, requiring an ever-increasing computational demand. To best make use of the limited computational resources available, we need to take shortcuts to increase calculation speed for both theory and experiment with minimal accuracy loss. Reduced Basis Methods (and Reduced Order Models in general) can help us compress the dynamics of nuclear systems by projecting onto low-dimensional spaces, effectively eliminating redundancies and speeding up calculations. In this talk we will give an overview of the methodology, share our recent results, and give a perspective on possible applications to both experiment and theory.

At the Spallation Neutron Source at Oak Ridge National Laboratory, research in collaboration with Jefferson Laboratory is ongoing to improve the accelerator and target operations using Machine Learning (ML). ML has the capability to see correlations in the data where other methods cannot and, through surrogate models, provide much faster simulation. After a short introduction to Machine Learning, the talk will discuss four use-cases: predicting upcoming errant beam pulses by analyzing data from a beam current monitor, improve the mercury filled high power target using surrogate modeling, use time-series ML methods to model the High Voltage Converter Modulator to estimate hardware components' remaining lifetimes, and use data-driven ML methods to improve the Cryogenic Moderator System response to beam on-off events. Initial results will be discussed, as well as the infra-structure that was set up to collect data and the tools to work with a remote team.

Lattice QCD methods provide non-perturbative access to observables in QCD. However, there are still many aspects of QCD yet to be revealed on the lattice due to the numerical difficulties called sign problems. In this talk, I will discuss recent developments on methods to alleviate or solve the real-time sign problem, which appears in Minkowski lattice calculations. Minkowski calculations are relevant to the phenomenological understanding of collider experiments, such as the hydrodynamic transport coefficients in QCD for heavy-ion collisions. Approaches to the real-time sign problem are different on classical and quantum computers, and this talk mainly focuses on classical algorithms. One well-established way to alleviate sign problems on a classical computer is the so-called manifold deformation method, in which one deforms the manifold of integration in the path integral to the complex plane, aiming for a milder sign problem. I will show that this method is expected to solve the real-time sign problem in bosonic lattice field theories. I will describe an algorithm based on machine learning to search for manifolds of integration with no sign problem.

The accelerator facility for Antiproton and Ion Research FAIR, one of the largest research infrastructures in Europe, is currently being built adjacent to the campus of GSI, Helmholtzzentrum f&#220r Schwerionenforschung, in Darmstadt. A suit of accelerators and storage rings will offer excellent research opportunities in hadron and nuclear physics, in atomic physics and nuclear astrophysics as well as in applied sciences like materials research, plasma physics and radiation biophysics with applications towards novel medical treatments and space science. FAIR is an international facility with 10 partner countries. More than 2500 scientists and engineers from more than 50 countries are involved in the preparation and definition of the research at FAIR. While the full potential of FAIR can only be exploited once the accelerators have been constructed and become operational, some of the experimental instrumentations are already available and are being utilized in a dedicated research program FAIR Phase-0 at GSI, exploiting the upgraded accelerator chain at GSI. The scientific potential of FAIR will be presented in this talk and the current status will be summarized with a special focus on the activities and the scientific results of FAIR Phase-0.

Stars are giant nuclear reactors responsible for the synthesis of every element beyond hydrogen and helium. They generate vast amounts of material through nuclear conversions acting over millions of years or in the blink of an eye, e.g., in quiescent stellar burning or in violent star explosions, respectively. Simulations of the internal stellar processes can reproduce the main features of the solar inventory, however the production of many naturally occurring nuclei is still a mystery. This applies in particular to the so-called p-nuclei arising from explosive nucleosynthesis, which suffers from large nuclear uncertainties. This seminar talk will introduce a novel experimental approach with the goal to provide data on nuclear key reactions and to produce strong constraints for explosive nucleosynthesis. The experimental campaign focuses on proton-capture reactions and is based on the production of radioactive ion beams at GSI, which are subsequently accumulated, cooled and decelerated in the heavy ion storage ring ESR. After years of development with stable beams, the first successful measurement has been conducted recently with radioactive beam, namely $^{118}$Te. The talk will discuss the experimental technique in detail, as well as the status and results of the recent and precursor experiments. Furthermore, an outlook to future experiments will be given also involving CRYRING, the new low-energy storage ring at GSI.

Committee: Witold Nazarewicz (Chairperson), Shanker Balasubramaniam, B. Alex Brown, Dean Lee, Brian O'Shea. Thesis is available at https://pa.msu.edu/academics/graduate-program/current-graduate-students/draft-dissertations-for-review/ - Select student name

The electroweak interaction in the Standard Model is described by a pure vector-axial-vector V A structure, but in principle, any Lorentz-invariant component is allowed. We have further improved on the tensor contribution limit set by our collaborations previous work examining the beta-neutrino correlation of trapped Lithium-8 with the Beta-decay Paul Trap (BPT) at Argonne National Laboratory. Utilizing a higher-statistics data set, alongside several experimental and simulation upgrades, we find |CT /CA|2 = 0.0012 ± 0.0019 (stat) ± 0.0028 (syst) at 1 sigma for the case of coupling to right-handed neutrinos, which is consistent with the Standard Model prediction and is the most stringent limit on tensor currents set to date in the low-energy regime. The extra statistics provided higher levels of precision that required careful treatment of the Beryllium-8 decay rates recoil order terms, which were determined using ab initio Symmetry Adapted No Core Shell Model (SA-NCSM) calculations.

The EIC currently being designed by a partnership between Brookhaven National Laboratory and Jefferson Lab will open exciting new frontiers for research in nuclear physics and QCD. The potential and the associated design requirements of the facility are laid out in detail in a comprehensive White Paper that has been compiled by the US nuclear physics community with world-wide support. An overview of the facility will be given, and latest design advances will be presented.

The screw compressor is a rotary positive displacement compressor, capable of compressing gas, vapors, and refrigerants. It is commonly used in various applications, including building and architecture, food, chemical process, pharmaceutical, metallurgical industries, refrigeration, air conditioning, vehicle superchargers and in cryogenic helium compression applications. The main characteristics that make the screw compressor attractive include high rotational speed, compactness, ability to maintain high efficiency over a wide range of operating conditions, long service life, and good reliability. An oil-flooded twin screw compressor is selected for investigation in the present work due to its reliability, large capacity, and capability to handle helium's high heat of compression. Oil-flooded screw compressors refers to the oil being injected into the compression process and mixed with helium. Benefits of injected oil are cooling the helium, creating sealing between rotors, lubrication, and higher performance. In helium systems, the loss of power within the compression system is roughly two-thirds. With such a high loss in power, it is imperative to understand the need for investigating the design and thermodynamic parameters that impact the overall performance of these machines. Initially, a review of different types of compressors is carried out to determine the best suited compressor for helium compression in this current work. A numerical model was created to simulate the compression process of the screw compressor. The model consists of three segments: Rotor curve generation, thermodynamic analysis, and performance prediction. The geometric data is a necessary input for the thermodynamic analysis however the thermodynamic analysis segment can be used for any rotor geometry. The thermodynamic analysis outputs the thermodynamic parameters as a function of male rotation angle of helium and oil. The performance prediction determines characteristics of performance such as the volumetric and isothermal efficiencies. The model was validated using a commercial software, which was developed on the basis of extensive screw compressor data. The model predicted performance with reasonable accuracy varying at extreme case with a maximum of 13% difference. Using the numerical model, the oil analysis in this thesis determined that the compressor performance is highly dependent on oil injection parameters. The isothermal efficiency spanned from 49.9% to 56.5% when adjusting the mass flow rate and oil injection position of the oil. Experimental results determined that the discharge temperature has the biggest impact on compressor performance. Persons with disabilities have the right to request and receive reasonable accommodation. Please call the Department of Mechanical Engineering at 355-5131 at least one day prior to the seminar; requests received after this date will be met when possible.

Nuclei are the heart of matter, and they are the fuel for reactions presented inside the core of stars. Simulating their physics starting from interactions among neutrons and protons requires immense computational resources. This is due to the exponential growth of the required basis to represent the many-body wavefunction. Quantum computing opens a new pathway to simulating these microscopic systems free from this classical limitation. In this talk, I will present two quantum algorithms we have developed for simulating dynamical and static properties. The first one implements the real time evolution to study nuclear scattering reactions with a hybrid quantum-classical approach. The spatial degrees of freedom are evolved classically, instead, the spin components are treated quantumly. The second algorithm is designed to study a quantum system's ground state through the Imaginary Time Propagation approach (also employed in classical Monte Carlo approaches). A crucial component of the method was to encode a non-unitarity operator in a unitary quantum circuit effectively. Both the algorithms are implemented in the real machine, and we will report our efforts to mitigate the noise of quantum processors. This work is based on references: [1] Holland, Wendt et al, Phys. Rev. A 101, 062307 [2] Turro et al, Phys. Rev. A 105, 022440

Committee: Artemis Spyrou (Chairperson), Scott Bogner, Paul Gueye, Jaideep Singh, Michael Thoennessen, Kirsten Tollefson. Thesis is available at https://pa.msu.edu/academics/graduate-program/current-graduate-students/draft-dissertations-for-review/ - Select student name

The neutron skin thickness in 208Pb has been linked via mean-field calculations to the equation of state of infinite nuclear matter, and consequently to the properties of neutron stars. At the same time, different mean field models yield a wide range of predicted values for the skin thickness, motivating its recent measurement via parity-violating electron scattering. I will present an alternative approach, utilizing the first ab initio calculations of 208Pb with nuclear interactions derived from chiral effective field theory. This approach provides two main advantages: it allows us to incorporate information from scattering and few-body data, and it provides a framework for comprehensive quantification of theoretical uncertainties. I will describe the developments which enabled these calculations, and discuss what the results tell us.

BOREXINO has recently measured for the first time the flux of neutrinos from the decay of radioactive 15O in the solar core, providing a unique direct way to determine the solar metallicity. The solar 15O abundance depends directly of the 14N(p,γ)15O reaction rate at solar temperatures, which largely relies on the extrapolation of reaction data obtained at higher energies. This extrapolation carries significant uncertainties due to the complex interference patterns near the particle threshold in 15O, which translates into a substantial uncertainty for a reliable prediction of the solar metallicty. We will present new data on low energy measurements at the CASPAR underground accelerator laboratory and lifetime measurements of 15O threshold states at the Nuclear Science Laboratory at Notre Dame to come to an improved prediction of the reaction rate at solar temperature.

Committee: Witold Nazarewicz (Chairperson), H. Metin Akulga, Shanker Balasubramaniam, Alexandra Gade, Heiko Hergert. Thesis is available at https://pa.msu.edu/academics/graduate-program/current-graduate-students/draft-dissertations-for-review/ - Select student name

Committee: Dean Lee (Chairperson), William Lynch Thomas Parker, Jeffrey Schenker, Vladimir Zelevinsky. Thesis is available at https://pa.msu.edu/academics/graduate-program/current-graduate-students/draft-dissertations-for-review/ - Select student name

Committee: Edward Brown (Chairperson), Sean Couch, Filomena Nunes, Joseph Rodriguez, Betty Tsang.

The Sixth Conference on NUCLEI and MESOSCOPIC Physics (NMP21) will be held at the Facility for Rare Isotope Beams / National Superconducting Cyclotron Laboratory (FRIB/NSCL) at Michigan State University (MSU), East Lansing, Michigan, USA We hope that NMP22 can be an effective stage for experts to interact and exchange ideas on a diverse set of topics and lead to cross-disciplinary collaborations. To meet the goal of the meeting, the focus talks will be 20 min & 10 min for discussion; the regular talks will be 10 min & 5 min for discussion; all talks will be a review-type presentations (including discussion time). The primary topics of interest are: Many-body quantum theory, Experiments with mesoscopic systems and exotic nuclei, Open and marginally stable mesoscopic systems, Quantum transport, Dynamic symmetries, Collectivity, chaos, and thermalization, Mesoscopic phase transitions, Superfluidity and superconductivity, Unconventional and topological systems, Fundamental symmetries in mesoscopic systems, Quantum computing and mesoscopic physics The abstract submission deadline is October 15, 2022, submit directly to Vladimir Zelevinsky zelevins@nscl.msu.edu. The Sixth Conference is supported by FRIB and Department of Physics and Astronomy at MSU. Contact NMP at nmp@nscl.msu.edu.

Nonlinear beam dynamics is one of the challenging research topics that may limit the performance of the accelerators. Both the theoretical analysis and computational method are power tools to reveal the mystery of the nonlinear world in accelerators. This talk will include two case studies of nonlinear dynamics problems using both approaches. Meanwhile, a preliminary application of the artificial intelligence algorithm in heavy-ion linac accelerators will also be presented.

The lighter heavy elements of the first r-process peak, between strontium and silver, which are observed in metal-poor stars, can be synthesized in the moderately neutron rich neutrino–driven ejecta of either core–collapse supernovae or neutron star mergers via the weak r–process [1]. This nucleosynthesis scenario exhibits uncertainties from the absence of experimental data from (α,xn) reactions on neutron–rich nuclei, which are currently based on statistical model estimates, and from the astrophysical conditions of the ejecta. We have performed a new impact study to identify the most important (α,xn) reactions that can affect the production of the lighter heavy elements under different astrophysical conditions, based on the work of Ref. [2] and using new, constrained (α,xn) reaction rates using the Atomki-V2 αOMP [3]. We have identified a list of relevant reactions that affect elemental abundance ratios that are observed in metal-poor stars [4]. Our results show how when reducing the nuclear physics uncertainties, we can use elemental abundance ratios to constrain the astrophysical conditions/environment. Plans to experimentally determine key (α,xn) reaction rates using the MUSIC detector at Argonne National Laboratory and the SECAR recoil separator at FRIB will be discussed. Via Zoom Webinar ID 942 7074 3060, Passcode (48824)

The stationary solutions of the Schrodinger equation with box or periodic boundaries show a clear correspondence to solutions found for the non-linear Gross-Pitaevskii equation (GPE) commonly used to model Bose-Einstein condensates. However, in the non-linear case there exists an additional class of solutions for periodic boundaries first identified by L.D. Carr et al. [1]. These nodeless solutions have no corresponding counterpart in the linear case. To fully classify these solutions and to understand their origin, we study the underlying algebraic geometry. Therefore, we treat both equations in the hydrodynamic framework, resulting in a first-order differential equation for the density determined by a quadratic polynomial in the linear case and by a cubic polynomial in the non-linear case, respectively. Our approach allows for a clear geometric interpretation and complete classification of the solution space in terms of the nature and location of the roots of these polynomials. Besides identifying oscillating, solitary wave and irregular solutions for the standard Gross-Pitaevskii equation we also include three-body interactions, commonly neglected. The solutions of these cubic-quintic GPE can be linked to solutions of the cubic GPE by means of a conformal duality. This new approach allows to establish correspondence between these two systems.

Scientific rationale: Recent developments in quantum information systems and technologies offer the possibility to address some of the most challenging large-scale problems in science, whether they are represented by complicated interacting quantum mechanical systems or classical systems. The last years have seen a rapid and exciting development in algorithms and quantum hardware. The emphasis of this summer school is to highlight, through a series of lectures and hands-on exercises and practice sessions, how quantum computing algorithms can be used to study nuclear few- and many-body problems of relevance for low-energy nuclear physics. And how quantum computing algorithms can aid in studying systems with increasingly many more degrees of freedom compared with more classical few- and many-body methods. Several quantum algorithms for solving quantum-mechanical few- and many-particle problems will be discussed. The lectures will start with the basic ideas of quantum computing. Thereafter, through examples from nuclear physics, we will elucidate how different quantum algorithms can be used to study these systems. The results from various quantum computing algorithms will be compared to standard methods like full configuration interaction theory, field theories on the lattice, in-medium similarity renormalization group and coupled cluster theories.

Committee: Remco Zegers (Chairperson), B. Alex Brown, Daniel Bazin, Hironori Iwasaki, Kendall Mahn. Thesis is available at https://pa.msu.edu/academics/graduate-program/current-graduate-students/draft-dissertations-for-review/ - Select student name

Committee: Witold Nazarewicz (Chairperson), Heiko Hergert, Matthew Hirn, Huey-Wen Lin, Hendrik Schatz.

We are pleased to announce the Fifteenth Workshop on Particle Correlations and Femtoscopy, WPCF 2022, to be held at the Facility for Rare Isotope Beams on the campus of Michigan State University. Science This event follows the tradition of previous editions by bringing together experts and other interested researchers in the field of particle-particle correlations and femtoscopy in nuclear and particle physics. The topics covered by the WPCF workshop concern the application of correlation measurements to discern the thermodynamic properties and evolution of emitting sources produced in heavy-ion collisions or nuclear reactions. This includes correlations from final-state interactions, phase transition dynamics, initial state fluctuations, collective flow, and from charge, energy or momentum conservation. A special session is devoted to the career of Pawel Danielewicz! Pawel2019 Topics: Femtoscopic correlations in heavy-ion collisions Charge fluctuations and charge balance functions Correlations of momentum and energy Collective flow and vorticity Correlations from fluctuating initial conditions Identifying resonances with correlations Phase coexistence and critical phenomena in heavy-ion collisions Statistical methodologies for interpreting experimental data and theoretical models Determining time scales in low-energy reactions Bayesian analysis of heterogeneous data and models These topics will be covered with talks selected from received abstracts. Participation and abstract submission by students and postdocs are strongly encouraged. More details on the program will be provided on the second circular and on the conference website. Registration and abstract submission: Registration will be available online at the WPCF webpage. Once registration is open, registrants can propose a presentation they might give by submitting an abstract on the website (see menu item "Abstract Submission"). The Organizing Committee also encourages anyone to nominate any other individual to present a talk by emailing suggestions to Kyle Brown (brownk@frib.msu.edu). The registration fee covers some lunches, coffee breaks, and two evening social gatherings. To register for WPCF go to "Registration"; To pay your registration go to Facility for Rare Isotope Beams - Store Home (cashnet.com). The registration fees for Senior Researchers are 0; PhD Students $ 100; grad students. Early registration ends on May 31, 2022. Important dates: April 20, 2022: Consideration of abstracts will begin. Early registration ends on June 30, 2022. Workshop Site: The Facility for Rare Isotope Beams, Michigan State University, East Lansing, MI 48824, USA. FRIB is a new major international user facility for nuclear physics, funded by the United States Department of Energy and by Michigan State University. First beams are arriving in May 2022. Generous funding for WPCF 2022 has been provided by the Facility for Rare Isotope Beams. FRIB is located on the campus of Michigan State University. One can fly directly to the East Lansing airport, typically after connecting from Detroit or Chicago. A shuttle service provides transportation from the Detroit airport (DTW) to downtown East Lansing in approximately two hours. Information about lodging is posted on the workshop website.

Committee: Andrea Shindler (Chairperson), Heiko Hergert, Oscar Naviliat-Cuncic, Thomas Parker C.-P. Yuan. Thesis is available at https://pa.msu.edu/academics/graduate-program/current-graduate-students/draft-dissertations-for-review/

Committee: Remco Zegers (Chairperson), Daniel Bazin, Scott Bogner, Edward Brown, Rachel Henderson.

Committee: Hironori Iwasaki (Physics Chairperson), Michael Murillo (CMSE Chairperson), Claudio Kopper, Dean Lee, Remco Zegers

Committee: Paul Gueye (Chairperson), Calem Hoffman Kendall Mahn, Filomena Nunes, Reinhard Schwienhorst

Committee: Hironori Iwasaki (Chairperson), B. Alex Brown, Laura Chomiuk, Wade Fisher, Alexandra Gade. Thesis is available at https://pa.msu.edu/academics/graduate-program/current-graduate-students/draft-dissertations-for-review/ - Select student name

The FRIB-TA Topical Program: Few-Body Clusters in Exotic Nuclei and Their Role in FRIB Experiments will be held at the Facility for Rare Isotope Beams (FRIB) on the campus of Michigan State University (MSU) in East Lansing, MI USA. The Topical Program is organized by the FRIB Theory Alliance. For selected participants we hope to provide partial support which may include lodging and meals. After registration has closed you will be contacted with the support we are able to provide. We will not provide support for transportation expenses.

Committee: Morten Hjorth-Jensen (Chairperson), Alexei Bazavov, Scott Bogner, Dean Lee Huey-Wen Lin, Johannes Pollanen. Thesis is available at https://pa.msu.edu/academics/graduate-program/current-graduate-students/draft-dissertations-for-review/ - Select student name

Committee: Christopher Wrede (Chairperson),Edward Brown, William Lynch, Filomena Nunes, Johannes Pollanen. Thesis is available at https://pa.msu.edu/academics/graduate-program/current-graduate-students/draft-dissertations-for-review/ - Select student name

Committee: Remco Zegers (Chairperson), Steven Lidia, Thesis Director, Hironori Iwasaki, Kei Nakamura, Peng Zhang

Accelerator complexes, such as FRIB, need precise tuning and fast optimization to achieve their goals. However, the discrepancies between the measurement and theory are commonly observed and become a significant obstacle to improving performance. The development of data-driven methods is an alternative way to tune and optimize the accelerator using high-fidelity measurement data. This work consists of analyzing these datasets and developing applications for heavy-ion accelerators. In addition, novel methods to include physics in machine learning algorithms will be developed in order to create models that can potentially extrapolate from the existing data and be more sample efficient. Committee: Yue Hao (Chairperson), Wade Fisher Dean Lee, Steven Lidia, Steven M. Lund.

Neutrinoless double beta decay nuclear matrix elements (NME) are the object of many theoretical calculation methods, and are very important for analysis and guidance of a large number of experimental efforts. However, there are large discrepancies between the NME values provided by different methods. In my talk I will discuss a statistical analysis of the 136Xe $0\nu\beta\beta$ NME using the interacting shell model, emphasizing the range of the NME probable values and its correlations with observables that can be obtained from the existing nuclear data. Based on this statistical analysis with three independent effective Hamiltonians we propose a common probability distribution function for the $0\nu\beta\beta$ NME, which can provide a range of NME values at 90% confidence level, with a mean value, and a standard deviation.

This talk describes our exploration of the chart of nuclides around and beyond the proton drip line. I will focus on ground and low-lying states that decay into four or more pieces. Our experimental technique utilizes the invariant-mass method which is particularly suited for understanding the decay channels of these levels. First, we will discuss states that process strong alpha-particle clustering in their density distributions with large deviations from spherical symmetry. While such states are well known in normal and neutron-rich nuclei, I will show proton-rich examples that can decay by emitting two-protons simultaneously. The second part of the talk will focus on the structure of nuclei as one goes further beyond the proton drip line towards the edge of existence of proton-rich isotopes. This is a region with multiple-proton emissions even in ground states. I will show examples of our latest identification of 3, 4, and 5 proton emitters.

High-current low-emittance CW electron beams are of great importance for the existing and future DOE facilities, medical, industrial and security applications. The CW superconducting radiofrequency (SRF) electron photoinjector is one of the most advanced, but also one of the most challenging, technologies promising to deliver such beams. While SRF technology is paving the way for future accelerators, the compatibility of the SRF environment with complex photocathodes remains on the forefront of modern accelerator science, and many important questions remain unanswered. In this seminar we will discuss the major components of an SRF photoinjector and review the existing designs and their specifics. We will dive into the details of the design and operation of the BNL 113 MHz SRF gun that has demonstrated exceptional performance delivering high charge electron bunches (up to 20 nC/bunch) and low transverse emittances, while operating for months with a single photocathode.

The Standard Model of particle physics describes virtually all measurements of elementary particles exquisitely well, and yet various astrophysical evidence points to new physics beyond the Standard Model. Recently it has been proposed to search for particles outside the Standard Model in an intermediate mass range (100 eV to 100 MeV) by means of precision isotope shift spectroscopy on narrow optical transitions. The exquisite precision of optical spectroscopy allows one to access high-energy physics with experiments at the eV scale. We report two nonlinearities in so-called King plots of measured isotope shifts for trapped Yb+ ions. Such nonlinearities can indicate physics beyond the Standard Model, or be due to higher-order nuclear effects within the Standard Model. We also discuss how future more precise measurements on more transitions, in combination with improved atomic-structure calculations, can be used to distinguish between effects within and outside the Standard Model, as well as determine nuclear parameters with high accuracy.

Committee: Artemisia Spyrou (Chairperson), Scott Bogner, Sean Liddick, Kendall Mahn, Brian O’Shea, Hendrik Schatz

Emmy Noether (1882-1935) was one of the most influential mathematicians of the last century. Her works and teachings left a lasting mark on modern algebra, opening new avenues for a modern structural perspective in mathematics. Noether began her studies at a time when women were only beginning to break down the barriers that prevented them from entering the doors of German universities. She eventually overcame even stronger resistance when she applied for the right to teach at a German university. It took her four years before she acquired that certification (Habilitation) in Gottingen on June 4, 1919, after submitting a thesis in which she solved one of the central problems in Einstein's general theory of relativity. To celebrate the centenary of this event and the career of a unique personality in the history of mathematics, the ensemble Portraittheater Vienna produced a biographical play, directed by Sandra Schuddekopf and starring Anita Zieher as Emmy. It opened on June 4, 2019, at the Freie Universitat Berlin. Afterward the play has been performed with great success at several different universities throughout Germany as well as the Theater Drachengasse in Vienna under the title "Mathematische Spaziergange mit Emmy Noether". Based on historical documents and events, the script was written by Sandra Schuddekopf and Anita Zieher in cooperation with the historians Mechthild Koreuber and David E. Rowe. "Diving into Math with Emmy Noether," the English-language variant, will be available for performances in other European countries as of 2021, and will go on tour in North America during the spring of 2022. Financial support for the original production was provided by three universities in Berlin (Freie Universitat, Humboldt-Universitat, Technische Universitat), and four other German universities (Erlangen-Nurnberg, Gottingen, Mainz, and Bielefeld).

Reliable theoretical predictions for beta-decay rates of neutron-rich nuclei are essential for r-process studies. Recent development of the proton-neutron finite amplitude method (pnFAM) [1] makes global beta-decay studies feasible within the nuclear density functional theory. In pnFAM calculations with the Skyrme energy density functional, the time-odd Skyrme couplings, isoscalar pairing, and effective axial-vector coupling constant strongly impact the results, but they are not constrained by the properties of even-even nuclei. Model calibration is thus necessary, and it is the first step towards the uncertainty quantification of beta-decay predictions. We perform both x2 optimization [2] and Bayesian model calibration with selected Gamow-Teller resonances and beta-decay half-lives, obtaining optimal parameter values as well as their uncertainties. A computational framework written in Python is developed to connect the pnFAM program with calibration routines. In the Bayesian model calibration, the Kennedy-O'Hagan framework [3] is adopted, where the physics model and discrepancy (model deficiency) are emulated by Gaussian processes (GPs). The two GPs can be fitted together (full Bayesian approach) or separately (modularization [4]); the latter is less computationally expensive, but the two approaches still produce consistent results. As for GP hyperparameters, a hierarchical prior structure is designed for better identifiability [5]. We also note that the parameter uncertainties are underestimated when the discrepancy term is ignored. In this work, comparisons between various calibration schemes provide insights into the use of statistical methods in nuclear physics.

Abstract: Contemporary accelerator lattices are primarily composed of linear focusing elements. These lattices suffer from a number of nonlinear perturbations which have negative effects on beam stability and intensity. Nonlinear integrable optics are a promising novel approach to mitigate these shortcomings. Prototypes of the nonlinear magnets that form such systems have been constructed and installed in the Integrable Optics Test Accelerator (IOTA). I aim to demonstrate the advantages of these optics using intense proton beams. Committee: Peter Ostroumov (Chairperson), Yue Hao, Hiro Iwasaki, Sasha Romanov, Chong-Yu Ruan, Remco Zegers

In 2020, The American Institute of Physics released its groundbreaking TEAM-UP Report, The Time is Now: Systemic Changes to Increase African Americans with Bachelor's Degrees in Physics & Astronomy following a rigorous research study by the TEAM-UP Task Force to understand the reasons for the persistent underrepresentation of African American students earning bachelor's degrees in these fields. In this talk, Ms. Knowles will present fndings from this study; discuss efforts to implement the report's recommendations among a select group of physics and astronomy departments committed to systemic change; share some strategies for supporting students; and reveal the next exciting steps for the TEAM-UP project.

The carbon fusion reaction is a crucial reaction in stellar evolution. Due to its complicated reaction mechanism, there is a large uncertainty in the reaction rate which limits our understanding to various stellar objects, such as massive stars, type Ia supernovae, and superbursts. In this talk, I will review the challenges and the recent progress in the study of the 12C+12C fusion reaction at stellar energies. The outlook for the future experimental studies will also be presented.

Light elements were produced in the first few minutes of the Universe through a sequence of nuclear reactions known as Big Bang nucleosynthesis (BBN). Among the light elements produced during BBN, deuterium is an excellent indicator of cosmological parameters because its abundance is highly sensitive to the primordial baryon density. Although astronomical observations of primordial deuterium abundance have reached percent accuracy, theoretical predictions based on BBN were hampered by large uncertainties on the cross-section of the deuterium burning D(p,g)3He reaction, before the LUNA measurement. I will report on the recent measurement of the D(p,g)3He cross section performed by the LUNA collaboration to an unprecedented precision of better than 3%. These results settled the most uncertain nuclear physics input to BBN calculations and substantially improve the reliability of using primordial abundances as probes of the physics of the early Universe. This success is tempered by lithium observations that are significantly discrepant with BBN predictions. I will briefly mention also the lithium problem.

Experience of developing online optimization methods, such as robust conjugate direction search (RCDS) and multi-generation Gaussian process optimizer (MG-GPO), and applying them to real-life accelerator problems will be presented. The applications include minimization of vertical emittance, optimization of storage ring dynamic aperture and lifetime, and optimization of linac transmission. Challenges of online optimization application and methods to address them will be discussed.

The SNS is presently the highest power spallation neutron source and superconducting linac operating worldwide. I will summarize the facility operational history and outline the present performance, touching also on the rich accelerator R&D program focused on high power beams. The ongoing power upgrade (PPU) from 1.4 to 2.8 MW will enable not only increased capability for neutron scattering but will open strategic opportunities for complementary facility utilization.

Mentoring of undergraduate students, graduate students, and postdoctoral researchers is an important part of any scientists' career. Research has shown that a good mentoring relationship can be one of the most important factors in determining students’ persistence in graduate school and recruitment of underrepresented students into the STEMM community. Although the importance of mentorship is understood, very few faculty have ever participated in a mentor training program and few structured training events are provided, especially for academics early in their career. This talk will discuss a recent National Academies' Report on the Science of Effective Mentorship, the benefits of positive mentoring experiences, and how you can integrate evidence-based mentoring practices into your community.

From the speaker: "The first quantum revolution brought us the great technological advances of the 20th century-the transistor, the laser, the atomic clock and the global positioning system (GPS). We now realize that this 20th-century hardware does not take full advantage of the power of quantum machines. A second quantum revolution is now underway based on our relatively new understanding of how information can be stored, manipulated, and communicated using strange quantum hardware that is neither fully digital nor fully analog. This talk will give a gentle introduction to the basic concepts that underlie this quantum information revolution and describe major challenges as well as recent remarkable experimental progress in the race to build quantum machines for computing, sensing and communication."

The Cathode Test Stand (CTS) at Los Alamos National Laboratory is used to evaluate field emission cathodes over a large range in pulse lengths. The CTS utilizes diagnostic tools such as E-dots and B-dots to take temporal voltage and current measurements. In addition, cathode and scintillator imaging is used in order to monitor the emission and current density (J(x,y)). Results have been produced using a velvet cathode over pulse lengths ranging from 0.5 µ to 1.5 µ. Along with experimental measurements, Trak is used to simulate the current CTS geometry. Here, the preliminary results will be presented along with comparisons to the Trak simulations.

Currently, event generators for neutrino experiments are the dominant systematic uncertainty for these experiments. Next-generation experiments (DUNE, SBND, and HyperK) will be systematics limited for the first time in neutrino physics. To ensure the success of these programs, advancements in lepton-nucleus event generators are required. Achilles is a new theorist-driven lepton-nucleus event generator developed with an emphasis on modularity. We have taken inspiration from the LHC event generator community to develop methods for handling BSM physics and intranuclear cascades (final state interactions). This approach for BSM allows for a quick implementation of almost completely arbitrary new physics models into the code for study at neutrino experiments. Additionally, Achilles is the first neutrino event generator to correctly handle all spin-correlations during the decay of final state particles. Achilles relies on state-of-the-art nuclear many-body approaches to model the interaction vertex and the intranuclear cascade, both benchmarked against the e4nu data in the quasielastic region. While currently only quasielastic and coherent scattering are implemented, the nuclear model used within Achilles has been validated for the meson-exchange current and resonance production. Finally, the future outlook for the Achilles generator will be discussed.

A wide range of international security practitioners and scholars have argued that we live in a 'second nuclear age,' one no longer dominated by the US-Soviet rivalry and the threat of large nuclear arsenals, but one that will return nuclear threats and challenges to prominence in an uncertain and far more unpredictable security environment. That environment will be defined by the proliferation of the most modern military capabilities to a much wider range of states, including China as an emergent superpower and dissatisfied states such as Iran and North Korea. Nuclear weapons have become a permanent factor in longstanding conflicts in South Asia and the Korean Peninsula, with other regional conflicts likely to be "nuclearized" in the coming decades. These new circumstances raise fundamental questions about the US security umbrella in a number of regions throughout the world that has discouraged proliferation among key allies, such as Japan and Germany. These new threats and challenges so far defy efforts to find comprehensive global or regional strategies of response, let alone find structures for bilateral or multilateral negotiations. Of greatest concern is the widespread assessment that this second nuclear age, largely free of the threat of a massive superpower nuclear war that defined the first nuclear age, is more likely to feature not only a wider range of nuclear crises with uncertain outcomes but a much a greater threat of nuclear use. This talk will explore the contours of this second nuclear age, especially in light of US national security, and explore the new FRIB initiative to bring issues related to nuclear weapons, arms control and nonproliferation to campus.

Different parameterizations of Skyrme energy density functionals show large variations in the stiffness of the neutron equation of state (EOS), making extrapolations to higher densities uncertain [1]. It has been shown that the difference in mirror pair charge radii is correlated with the L parameter, which is the slope of the symmetry energy in the nuclear EOS [2]. By placing constraints on L, the neutron equation of state can thereby be constrained. In the present study, the charge radius of neutron-deficient 54Ni was determined for the first time using collinear laser spectroscopy at the BEam COoling and LAser spectroscopy (BECOLA) facility [3,4] at NSCL/MSU. Using the difference in mirror pair charge radii between 54Ni and 54Fe, a constraint of 20 ≤ L ≤ 70 MeV has been placed [5], consistent with results from the gravitational wave event of the GW170817 neutron star merger [6] and barely consistent with those from PREX-2 [7]. Constraints on the neutron skin for 48Ca from this experiment are in agreement with the preliminary CREX results released at DNP 2021, implying a "soft" EOS and contradictory to the PREX results. In addition to the experimental results, a new trend analysis will be discussed, which evaluates the reliability of the difference in mirror charge radii and its stringency on L parameter constraints [8]. *Work supported in part by NSF Grant No. PHY-14-30152, No. PHY-15-65546, No. PHY-18-11855, No. PHY-21-10365 and No. PHY-21-11185, and by the U.S. DOE Office of Science, Office of Nuclear Physics under Award No. DE-FG02-92ER40750, and by the DFG Project-ID 279384907-SFB 1245. [1] B. A. Brown, Phys. Rev. Lett. 85, 5296 (2000). [2] B. A. Brown, Phys. Rev. Lett. 119, 122502 (2017). [3] K. Minamisono et al., Nucl. Instrum. Methods Phys. Res., Sect. A 709, 85 (2013). [4] D. M. Rossi et al. Rev. Sci. Instrum. 85, 093503 (2014) [5] S. V. Pineda et al. Phys. Rev. Lett. 127, 182503 (2021). [6] C. Raithel and F. Özel, Ap. J. 885:121 (2019). [7] B. T. Reed et al., Phys. Rev. Lett. 126, 172503 (2021). [8] P.-G. Reinhard and W. Nazarewicz, Phys. Rev. C 105, L021301 (2022).

Though the world has changed dramatically since the advent of nuclear weapons 77 years ago, the strategy for preventing the use of nuclear weapons-nuclear deterrence-has changed very little. This strategy was created for a slow, analog, bi-polar world, and today's world is far more complex, featuring heightened tension between the nine nuclear possessor states, more lethal, hypersonic speed nuclear weapons, and many pathways to nuclear use that deterrence was never designed to address. The challenge is to push the frontiers of nuclear innovation in both the policy and technology spheres and to design a more effective strategy for reducing the risks of nuclear use. A big part of any new strategy should include innovation of new technologies and procedures for controlling nuclear weapons technologies worldwide. This talk will outline what such a new nuclear technology control regime might look like and how places of cutting-edge research and training might contribute to that regime.

The discovery of radioactive 26Al via the observation of the 1809-keV γ ray in 1982 is one of the most famous pieces of evidence of on-going nucleosynthesis in the cosmos. The 26Al is likely to be produced dominantly in massive stars and supernovae. Nevertheless, a number of additional sources such as classical novae and AGB stars may still contribute considerably to the production of 26Al. Thus, up to 29% of the total observed 26Al abundance is predicted to have a nova origin. The 25Al(p,γ)26Si reaction is a possible means of bypassing the production of 26Al in classical nova. However, the lack of experimental data has hindered the ability to accurately model the influence of this reaction in such environments. In this seminar, I will present results which illustrate two complementary experimental domains: Mass measurement and γ-ray spectroscopy. In the 25Al(p, γ)26Si reaction, proton capture is dominated by resonant capture to a few states above the proton threshold in 26Si. The mass values of 25Al and 26Si have an exponential contribution to the total resonant proton capture rate in 26Si. The mass of 25Al was precisely determined via Penning traps measurements at the IGISOL facility of the University of Jyvaskyla, Finland. Additionally, a recent experiment at Argonne National Laboratory, USA was performed to identify the resonant states in 26Si, via their γ-ray decays, using the unique GRETINA+FMA setup. The results of this latter experiment agreed with a recent detailed spectroscopy study of the 26Si mirror nucleus, 26Mg in which evidence for a new l=1 resonance in the 25Al+p system was presented. However, despite an increase of the reaction rate at the low temperature range of novae, the final ejected abundance of 26Al from classical novae remains largely unaffected. Using these results in galactic chemical evolution calculation, the contribution of classical novae to the abundance of 26Al was estimated to be only 10% to the observed 26Al in the Galaxy.

Superconducting accelerator magnets are the driving technology for the science reach of future colliders, dictating the energy reach of a collider and dominating a facility's cost. As the international community prepares to implement the relatively high-field superconductor Nb3Sn into a collider for the first time with the LHC Luminosity Upgrade project, the research community is working hard to prepare the next generation of magnet technology, targeting ever higher fields, larger apertures, and the use of next-generation high temperature superconductors. We will review the state of the art in high field magnets, with particular attention to the needs of the accelerator community. We will then describe the primary research directions being pursued, and highlight specific advances in modeling, diagnostics, materials and magnet testing. Important distinctions between the magnet technology associated with each of the primary commercial superconductors, namely NbTi, Nb3Sn, Bi2212, and REBCO, will be explored. Finally we will summarize the directions being considered by the collider community, and summarize the magnet research roadmap we have developed to advance our field and address the physics community needs.

Neutron stars play a unique role in determining the nature of hot and dense matter. For example, observations of quiescent neutron stars provide a unique insight into cold matter at densities larger than the nuclear saturation density. Additionally, neutron star mergers potentially probe hot neutron-rich matter over a wide range of densities. In the first part of this talk, I show how we are combining neutron star observations to obtain the equation of state of cold strongly-interacting matter and the neutron star mass-radius curve. In the second part, we combine neutron star observations, recent results from nuclear theory, and a recent analysis of nuclear structure experiments to develop a world-class equation of state table for core-collapse supernovae and neutron star mergers. Finally, I present a new analysis of FRIB nuclear mass measurements based on Bayesian decision theory.

The future Electron-Ion Collider (EIC) located at Brookhaven National Laboratory will collide 5-18 GeV electrons with protons of energies up to 275 GeV, as well as light, medium, and heavy nuclei with energies of approximately 100 GeV/nucleon. Using these high-energy beams, the EIC will make very important contributions to our knowledge of the nucleon’s spin and three-dimensional structure, the origin of hadronic mass, and the potential onset of non-linear QCD dynamics at high energy. As the EIC project moves forward, dedicated Monte Carlo simulation tools are being developed in parallel to model these high-energy electron-nucleus collisions. Simulation studies conducted with one of these models – the Benchmark eA Generator for LEptoproduction (BeAGLE) – suggest that the electron-nucleus collision will create a thermalized, excited residual nucleus. Interestingly, the creation of this residual nucleus generally follows a simple abrasion model. Passing this residual nucleus into either the code FLUKA or the code ABLA07 allows one to study the nuclear fragments created during the evaporation/fission de-excitation. We will present simulation studies of electron-nucleus scattering at EIC energies and discuss the possibility of creating and detecting high-energy nuclear fragments at the EIC, as well as opportunities to measure these fragments in coincidence with de-excitation photons. Due to the high energies and unique kinematics of the EIC, these measurements will allow studies of reaction mechanisms, the simultaneous detection and reconstruction of multiple fission fragments, direct detection of heavy fragments with ns lifetimes, and measurements of de-excitation photons with low backgrounds. Our hope is that measurements made at the EIC a decade from now can complement current and future measurements at dedicated rare isotope facilities.

Core-collapse supernovae (CCSNe) are some of the brightest, most energetic events in the universe. In order to model these phenomena accurately, we need to have a diverse range of physics such as neutrino transport and neutrino interactions, general-relativistic gravity, detailed equations of state (EoS) of dense matter, magnetohydrodynamic (MHD) and detailed progenitor models. The advent of powerful supercomputers and the development of numerical methods has allowed us to simulate these explosions in great detail, and in recent years, in full 3D geometry. However, aside from the modelling of rare hypernova progenitors (where rapid rotation and very strong magnetic fields are imposed), magnetic fields haven’t been explored extensively for the neutrino-driven explosion mechanism. In this seminar, I will focus primarily on the inclusion of magnetic fields in modelling these events. I will present the first multidimensional simulation of magnetic fields in the final phases of oxygen shell burning, which provides a first step in understanding what realistic magnetic field strengths and geometries should be in CCSNe progenitors. I will then explore some of the first 3D simulations of magnetic neutrino-driven supernovae, and explain how this inclusion can impact the dynamics of the supernova as well as their remnants.

Abstract: The Fermilab Booster is an operational proton synchrotron which features the world's most extreme space-charge forces. With the upcoming PIP-II linac project for the ambitious DUNE/LBNF program, the Booster will need to cut uncontrolled particle losses by half while simultaneously accelerating 50% more charge. Several areas of transverse beam dynamics in the Booster are discussed. The vertical half-integer resonance leads to rapid emittance growth and early beam loss in the Booster, but my recent work in correcting the resonance has also revealed an unexpected benefit. Electron cloud effects in the gradient dipole magnets are also being investigated. Advanced ML algorithms are proposed for robust operations with the Booster's idiosyncratic optics. Lastly, I discuss how critical design questions for future intense rings can be informed by the empirical study of space-charge and machine resonances.

Committee: Andrea Shindler (Chairperson), Alexei Bazavov, Dean Lee, Carlo Piermarocchi, Jaideep Singh Thesis is available at https://pa.msu.edu/academics/graduate-program/current-graduate-students/draft-dissertations-for-review/ - Select student name

As part of the U.S. 2023 Nuclear Physics Long Range Planning process, the U.S. QCD Community met for 2.5 days on September 23-25, 2022 at MIT to discuss the status and plans for QCD research in the coming decade and beyond. The meeting attracted 423 registrants, of which about 200 were in person. There were 105 individual presentations and an overview will be presented. Recommendations and initiatives were developed at the meeting and the registrants were surveyed as to their opinions. The results of the survey will be presented.

White dwarfs are stellar embers that simply cool down for the rest of time, eventually freezing into a solid state. This predictable evolution makes them precise cosmic clocks; they have been used for decades to measure the ages of stellar populations. But data from the Gaia space observatory is now calling into question the accuracy of this age dating technique. The cooling process appears to be much more delayed by the onset of crystallization than predicted by current models. I will present my recent work on the physics of core crystallization. In particular, I will explain how the fractionation of 22Ne can eliminate the current disagreement between models and observations. I will also discuss our current work on 3D hydrodynamics simulations of red giant stars with the aim of better constraining the interior composition of white dwarfs.

This seminar will cover completed and planned experiments on single electron tracking at the Integrable Optics Test Accelerator (IOTA, Fermilab). Conducted experiments have proven the feasibility of the complete 6-dimensional tracking of an electron. As the next step, we plan to demonstrate it experimentally. Direct 6-dimensional tracking of a single electron in a storage ring will enable a new class of beam diagnostic technologies. It will allow a high-precision characterization of single-particle dynamics. To track a charged particle we detect single photons randomly emitted over many turns. State-of-the-art technologies of photon detection have temporal and spatial resolution sufficient for high-precision tracking if coupled with advanced analysis algorithms. Complete tracking of a point-like object will enable the first measurements of single-particle dynamical properties, including dynamical invariants, amplitude-dependent oscillation frequencies, and chaotic behavior. These single-particle measurements will be employed for long-term tracking simulations, training of AI/ML algorithms, and ultimately for precise predictions of dynamics in the present and future accelerators.

Dance Exchange's Of Equal Place: Isotopes in Motion is an exhilarating performance that combines dance, video, and physics featuring professional dancers and guest performances by local youth. Inspired by Dance Exchange's critically acclaimed, The Matter of Origins, the show highlights the wonders of science and illuminates the research at the Facility for Rare Isotope Beams (FRIB). Following the performance, audience members are invited to participate in a series of activities exploring dance, physics, and FRIB. Performed by Dance Exchange and Happendance. Led by Creative Director Keith Thompson and Director of Creative Engagement Ami Dowden-Fant, in collaboration with Wharton Center Institute for Arts & Creativity and Women & Minorities in the Physical Sciences. Underwritten by the Facility for Rare Isotope Beams at Michigan State University with additional support by MSU University Outreach and Engagement, Science and Society at MSU, and Office of the Vice President for Research and Innovation.

The demand for the cytotoxic radionuclide actinium-225 (225Ac) with a relatively longer half-life of 9.920 days is rapidly increasing lately for use in cancer treatments. This radionuclide is especially attractive for targeted alpha therapy treatment (TAT) due to its high linear energy transfer and the four alpha emissions in its decay chain [1]. However, the current 225Ac supply cannot meet this newfound demand for numerous pre-clinical and clinical trials, much less any projected treatments [2]. To meet this growing need, multiple private and public entities are examining numerous 225Ac production pathways. Potential methods include electron, proton, or neutron irradiation of radium or natural thorium targets to produce 225Ac either directly or indirectly via a 225Ra/225Ac generator. Despite the many promising production methods, logistical challenges persist to produce a viable method to produce this valuable radionuclide in the necessary quantities. Here, the production methods and the viability of each will be considered. References: [1] M. Miederere, D.A. Scheinberg, and M.R. McDevitt, Advanced Drug Delivery Reviews 60 (2008). [2] J.W. Engle, Current Radiopharmaceuticals 11 (2018). Join Zoom Meeting https://msu.zoom.us/j/97429900849 Meeting ID: 974 2990 0849 Passcode: 814133

The study of radioactive molecules receives increasing attention due to their enhanced sensitivity to fundamental symmetry violations and Beyond Standard Model physics. In particular, 225RaF has been proposed as powerful probe due to its enhanced Schiff-moment. While the principle advantage of such systems is known for more than 30 years [1], the progress in the field relies on the development of novel instruments and the availability of suitable radioisotopes. At the Facility for Rare Isotope Beams (FRIB), the latter is being addressed by development of isotope harvesting techniques [2]. Within this Research Discussion, we introduce the in-design FRIB-EDM3 instrument. The setup was designed to study polar radioactive molecules (like RaF) in transparent cryogenic solids by laser spectroscopy with the EDM3-method [3]. The efficient ionization of harvested radioisotopes from aqueous phase is pursued with a spray-ionization method [4]. Subsequently, the molecular ion beam is analyzed by mass-to-charge ratio by a quadrupole mass filter and neutralized in a charge-exchange cell before its implantation in a solid argon matrix. We will present the design of the instrument and report on the progress of its construction. References: [1] T.A. Isaev et al., Lasercooled radium monofluoride: A molecular all-in-one probe for new physics (2013), https://arxiv.org/abs/1302.5682 [2] E.P. Abel et al., J. Phys. G: Nucl. Part. Phys. 46, 100501 (2019) [3] A.C. Vutha et al. (2018), 10.48550/ARXIV.1806.06774 [4] R.T. Kelly et al., Mass Spectrometry Reviews 29, 294 (2010)

Details of the explosion mechanism of core-collapse supernovae (CCSNe) are not yet fully understood. There is now an increasing number of successful examples of reproducing explosions in the first-principles simulations, showing a slow increase of explosion energy. However, it was recently pointed out that the growth rates of the explosion energy of these simulations are insufficient to produce enough 56Ni mass to account for observations. Radioisotope 56Ni is an important product, which drives supernova brightness. However, the amount of 56Ni often goes unnoticed by the explosion mechanism community because it is difficult to estimate at first glance from numerical data. We refer to this issue as the "nickel mass problem" (56Ni problem, hereafter; Sawada et al. 2019, Suwa et al. 2019, Sawada & Suwa 2021). In this talk, I will start with the basics of elemental synthesis of the radioisotope 56Ni in supernova explosions and the mechanism of supernova explosions, and will finally discuss "56Ni problem", focusing on my own study.

Accelerator physics is a strongly applied discipline, with SRF Cryomodules being a extreme example. Delivery and successful operation of cryomodules requires simultaneous performance of dozens of specialized systems and disciplines. Unexpected issues are inevitable during a large SRF project, and it is critical to have a strong, cross-discipline team to meet these challenges. This talk will highlight several examples of these challenges based on experience at Fermilab on the LCLS-II and PIP-II projects, including failures and lessons learned from transportation, testing, and operations.

The p-process of nucleosynthesis is responsible for the production of about 30 heavy, neutron-deficient nuclei that cannot be formed by the r- or s- processes. A version of the p-process called the γ-process is believed to occur by photodisintegration of r- and s- process seed nuclei in the shock-wave of a supernova, and is favored to produce most of the p nuclei. To understand this process, our strategy is to perform targeted measurements of key reactions that have a direct effect on the nucleosynthesis of one or more p-nuclides in astrophysical models, and can calibrate statistical model calculations of many other reactions in the region. Direct cross-section measurements of key branch points in the reaction network are typically performed in the reverse direction, have difficulty covering the Gamow window, and are limited by their inability to populate excited states in the target nuclei. The Particle X-ray Coincidence Technique (PXCT) may be used to measure nuclear lifetimes of unbound states by detecting the X-rays from electron capture (EC) decay and coincident delayed proton or alpha decay. The characteristic X-ray energy is determined by the Z of the X-ray emitter and therefore informs us of the sequence of emissions. Because the lifetime of charged particle emission is comparable to that of X-ray emission, PXCT can be used to determine the lifetime of the charged particle emitting state. We propose to measure the EC decay of 110Sb at FRIB using the PXCT technique to statistically determine the lifetimes of 110Sn unbound states relevant to the 110Sn(γ,α)106Cd reaction. With this technique, we can access excited states in both the initial and final nuclei involved in the astrophysical reaction, which is not possible in direct measurements. These partial branching ratios can be measured with our two, large volume HPGe detectors surrounding the chamber that houses a Si telescope and a planar Ge detector, for charged particle and X-Ray detection, respectively. The design and purchasing of this experimental setup is complete and the fabrication is in progress. The results will complement existing direct cross-section measurements of 106Cd(α,γ)110Sn with information on transitions to excited 106Cd states, and provide valuable information on the α optical model potentials of nuclei in that region. Additionally, our method applied to this case is optimal for alpha energy ranges in a considerable portion of the Gamow window inaccessible via direct measurements. Simulations demonstrate the sensitivity of our setup to lifetimes and branching ratios which will provide more accurate experimental p-process reaction rates. Committee: Christopher Wrede ( Chairperson), Jonas Becker, Sean Couch, Alexandra Gade, Filomena Nunes.

FRIB Graduate Research Assistant Different parameterizations of Skyrme energy density functionals show large variations in the stiffness of the neutron equation of state (EOS), making extrapolations to higher densities uncertain [1]. It has been shown that the difference in mirror pair charge radii is correlated with the L parameter, which is the slope of the symmetry energy in the nuclear EOS [2]. By placing constraints on L, the neutron equation of state can thereby be constrained. In the present study, the charge radius of neutron-deficient 54Ni was determined for the first time using collinear laser spectroscopy at the BEam COoling and LAser spectroscopy (BECOLA) facility [3,4] at NSCL/MSU. Using the difference in mirror pair charge radii between 54Ni and 54Fe, a constraint of 21 less than or equal to L les than or equal to 88 MeV has been placed [5], consistent with results from the gravitational wave event of the GW170817 neutron star merger [6] and barely consistent with those from PREX-2 [7]. Constraints on the neutron skin for 48Ca from this experiment are in agreement with the CREX results [8] implying a soft EOS and in contrast to the stiff PREX results. In addition to the experimental results, the importance of model dependence and a new trend analysis will be discussed, which evaluates the reliability of the difference in mirror charge radii as a good isovector indicator [9]. *Work supported in part by NSF Grant No. PHY-14-30152, No. PHY-15-65546, No. PHY-18-11855, No. PHY-21-10365 and No. PHY-21-11185, and by the U.S. DOE Office of Science, Office of Nuclear Physics under Award No. DE-FG02-92ER40750, and by the DFG Project-ID 279384907 SFB 1245. Zoom Information: https://msu.zoom.us/j/96590786756 Meeting ID: 965 9078 6756 Passcode: 982225 Committee: Kei Minamisono, Sean Liddick, B. Alex Brown, Gregory Severin

The National Nuclear Security Administration (NNSA) seeks to minimize the risk of hostile states and non-state actors from acquiring nuclear material for an improvised nuclear device. NNSA accomplishes this goal by working with partners to eliminate the need for, presence of, or production of weapons-usable nuclear material. In my talk, I will provide an overview of the NNSA’s Office of Material Disposition, which pursues threat reduction through the permanent disposition of Highly Enriched Uranium and Surplus Plutonium, so it will never again be used to build a nuclear weapon. I will also briefly discuss my transition from basic science research to the NNSA and provide some resources for students who are interested in working in the nuclear security enterprise.

One of the biggest questions in nuclear astrophysics regards how elements are synthesized in stellar environments. Observations of astrophysical phenomena provide us with evidence for different nucleosynthesis processes, and modelling these astrophysical scenarios requires a detailed description of the complex nuclear physics that is involved. Radioactive decay, nuclear reactions, and the properties of individual nuclei are required to fully understand the origin of the elements, and substantial experimental and theoretical progress has been made to address this question. On the neutron-rich side of stability, neutron-capture processes such as the slow (s), intermediate (i), and rapid (r) processes play a pivotal role in our understanding of the origin of heavy elements. Direct neutron-capture measurements are infeasible for the short-lived nuclei involved in these processes, and therefore indirect neutron-capture techniques are needed. In this presentation I will discuss indirect neutron-capture techniques that have been developed over the last few years, namely the β-Oslo method and the Surrogate Reaction method, and how they can be applied across the nuclear chart at radioactive beam facilities.

The study of exotic nuclei will offer direct insights into fundamental questions in physics such as the creation of heavy elements and the structure and formation of neutron stars. As rare isotope beam facilities around the world extend their reach to increasingly exotic regions of the nuclear chart, reliable reaction theory models with robust error estimates will be crucial to drive scientific discovery. As a key input to many reaction models, optical potentials play a central role in the analysis of a wide range of nuclear reaction experiments, yet to date the most widely applicable optical potentials are largely phenomenological and lack uncertainty quantification. The recently constructed Whitehead-Lim-Holt (WLH) global optical potential, on the other hand, offers a microscopic description of nucleon-nucleus scattering over a large range of isotopes and scattering energies with error estimates from chiral effective field theory. In this talk, I will outline several applications and extensions of the WLH global optical potential that lay a groundwork for the study of reactions with rare isotopes.

Although computationally expensive, Bayesian uncertainty quantification is crucial for the theory-experiment cycle, especially at laboratories such as FRIB with so many possible research opportunities. We present two frameworks to help foster this cycle: one for accelerating experimental design by propagating uncertainties through transfer functions, and one for streamlining model calibration through a reduced basis emulator. This emulator removes redundancies and goes straight to the point, like this abstract does.

Weakly-bound nuclei are observed to have a suppression of complete fusion compared to theory when reacting with heavy targets at above-barrier energies. This phenomenon is thought to be partially due to projectile breakup into charged clusters and these reaction dynamics are further complicated away from stability. We commissioned FABLE (Fusion Array for Breakup of Light Elements), a reconfigurable array of annular Si telescopes capable of measuring charged fragments with high angular separation in coincidence, to measure the breakup, incomplete fusion, and complete fusion of 7Be at above-barrier energies as a first step towards better understanding complete fusion suppression away from stability. Committee: Alexandra Gade (Chairperson), Kaitlin Cook, Wade Fisher, Paul Gueye, Morten Hjorth-Jensen, Remco Zegers

Nuclear reactions play a critical role in probing the properties of atomic nuclei, production of elements in astrophysical environments, as well as national security applications. For example, a class of reactions known as "transfer reactions" are useful in determining spins, parities, and spectroscopic factors for specific nuclear states. In particular, deuteron-induced transfer reactions on rare isotopes have been used to probe single-particle levels of nuclei as well as to indirectly infer neutron-capture rates needed to simulate the synthesis of heavy elements in cataclysmic astrophysical events. Since the observables measured in reaction experiments are cross sections, extracting structure properties as well as the relevant neutron-capture rates requires a reliable reaction theory. In light of reaction measurements taking place in rare isotope facilities around the world and in anticipation of the large influx of data from FRIB, theories that are suitable for the description of reactions involving exotic nuclei are needed. Using the example of deuteron-induced reactions, I will discuss the importance of a dependable reaction theory for translating experimental measurements into the desired nuclear information. I will also discuss advances in the three-body (neutron + proton + nucleus) description of such reactions as well as ab initio approaches that seek a solution of the many-body scattering problem, starting from nucleon-nucleon potentials derived from chiral effective field theory. Finally, I will give my perspective on efforts to construct predictive reaction theories that can be reliably applied to nuclei closer to the dripline by focusing on integrating few-body reaction dynamics with ab initio methods.

Ab initio models are built upon realistic internucleon interactions, which empowers them with predictive capability. The ab initio symmetry-adapted no-core shell model (SA-NCSM) utilizes emergent symmetries in nuclei to reduce the dimensionality of the model space. This, in turn, allows one to reproduce the low-energy nuclear dynamics with only a small fraction of the model space, hence making solutions to heavier nuclei and ultralarge model spaces feasible. This work discusses calculations of beta decays and nucleon-nucleus spectroscopic overlaps using the SA-NCSM. I will further discus how these calculations can be utilized in construction of nuclear structure-based optical potentials vital for the studies of reactions involving rare isotopes.

Precise and predictive calculations of the atomic nuclei from realistic nuclear force can help us to explain the exotic nuclear phenomena, understand the fundamental theory, explore the limit of stability, and study the state of the neutron star. The advances in computational power, emerging machine learning technology, and the development of many-body methods make it possible to perform uncertainty quantification and sensitivity analyses in nuclear structure calculations. It can help us to understand how the fundamental interaction leads to the emergence of various exotic phenomena observed from the facility of rare isotope beams and provide essential input for future experiment design. In this talk, I will report on the progress of the ab-initio coupled-cluster method in describing spherical and deformed atomic nuclei. I will also introduce the quantified predictions of the neutron skin thickness of ²⁰⁸Pb and the drip line of oxygen isotopes."

In unresolved galaxies, age, metallicity, α/Fe enhancement of the stellar populations, as well as the IMF and the mass can be constrained via full spectra fitting or via line-strength index analysis. The Lick/IDS system is a prime example of line-strength spectroscopic indices that are sensitive to these parameters in the optical domain. In the Near-Infrared (NIR), where the upcoming generation of telescopes will primarily observe, we lack such a system, and the full spect ral fitting technique is not yet reliable. To study the properties of the stellar populations in the NIR for unresolved galaxies, a new line-strength index system has been defined, initially for the most recent releases of the stellar libraries. The new indices are tested and calibrated using the spectra of the central regions of nearby galaxies of the highest quality, both in S/N and wavelength range. New mass, age, metallicity, α/Fe and IMF indicators are introduced and compared to the most recent empirical SSP models. The new NIR index system will be very useful for characterizing the stellar populations of galaxies, and it sets new constraints for a fine-tuning of the SSP models, which are still unable to reproduce the yields of the AGB stars, whose light dominates in the NIR.

Outline: Introduction, Why Build a Particle Accelerator, A Brief History of Linac Construction, How It Works (orig operation & design), Systems Upgrades Improves Performance, Brief Video Tour, Summary & Questions