Facility for Rare Isotope Beams

A central result from the RHIC experimental program is the discovery that the medium produced in relativistic heavy ion collisions from a range of collision energies behaves as a nearly-perfect fluid. This remarkable property is manifested in a collective behavior of the particles emitted from the collisions, known as "flow". In non-central collisions, the initial reaction zone is spatially asymmetric. The ability of the system to convert the initial spatial anisotropy into a final-state momentum anisotropy is directly related to its ability to flow without dissipation. The flow strength is measured through a Fourier expansion of the hadron azimuthal distributions with respect to the reaction plane. The evolution of the flow with collision energy provides a challenging test for our understanding of the quark-gluon plasma properties. I will review recent results of harmonic flow measurements from RHIC and LHC spanning two orders of magnitude in collision energies and discuss the "perfect fluid" and its dynamical evolution.

Simple predictions of many chemical properties can be determined based on the location of an element on the periodic table. As atomic number increases, relativistic electron effects become important and may significantly alter a heavy element’s chemical behavior, causing divergence from expectations derived from periodic trends. Transactnide chemistry seeks to determine the degree to which the heaviest elements act according to their positions on the periodic table. Element 112 (copernicium) and element 114 (flerovium) have recently been studied in gas-phase chemistry experiments [1, 2]. After production of the isotopes of interest, volatile reaction products were separated from non-volatile products using the In situ Volatilization and Online detection (IVO) gas chromatographic separation system [3]. The heavy reaction products were detected by the Cryo-OnLine Detector (COLD) that consists of 32 pairs of silicon detectors of which half the detectors have a gold coating [2]. The enthalpies of sublimation of elements 112 and 114 have been determined as quantitative measurements of their volatilities. The enthalpy of sublimation of element 112, ΔHsubl(E112), has been determined to be 38+10-12 kJ mol-1, which suggests it behaves similarly to other members of Group 12 of the periodic table [1]. Although the results are somewhat controversial, in a separate experiment, ΔHsubl(E114) was determined to be 23+22-8 kJ mol-1, which indicates that unlike other members of Group 14, element 114 is inert, similar to a noble gas [2]. [1] R. Eichler et al., Nature (London) 447, 72 (2007). [2] R. Eichler et al., Radiochim Acta 98, 133 (2010). [3] Ch.E. Düllmann et al., Nucl. Instrum. Methods Phys. Res., Sect. A 479 631 (2002).

Recent extensions of the energy density functional approach use the relativistic framework in combination with advancements of Landau - Migdal theory for Fermi liquid in Green’s function techniques. The set of the developed self-consistent models is applied to shell structure and spectroscopic factors, isovector and isoscalar giant and soft modes, Gamow-Teller and spin-dipole resonances in ordinary and exotic nuclei. Compared to previously existing microscopic models, the quality of description of the nuclear structure phenomena is improved substantially. It is shown that microscopic nature, consistency and universality of the developed methods make them an ideal tool to interpret experimental data for exotic nuclei and to provide the nuclear physics input for astrophysical applications.

The doubly magic nature of ⁵⁶Ni can be probed by studying the properties of nuclei one nucleon removed from ⁵⁶Ni. ⁵⁷Cu can be modeled as a ⁵⁶Ni core plus a proton in the 2p_3/2 state. The nuclear magnetic dipole moment for ⁵⁷Cu, carries information about the spin and angular momentum components of the nuclear state wavefunction. Therefore, the magnetic moment serves as a test of the goodness of the N=Z=28 closed shells [1]. Atomic laser spectroscopy is one method that can be used to determine the nuclear magnetic dipole moment through the observed hyperfine spectrum. Collinear laser spectroscopy is the traditional method of choice for laser spectroscopy performed on rare isotopes. In-gas-cell laser spectroscopy is a recently developed technique that is effective for the study of isotopes with low production rates, such as ⁵⁷Cu. However, the resonance linewidths observed using this technique suffer from the effect of pressure broadening. The atomic hyperfine spectrum of ⁵⁷Cu was recorded at LISOL (Leuven Isotope Separator On-Line) using in-gas-cell laser spectroscopy. The magnetic moment was extracted from the hyperfine spectrum to be +2.582(7)n.m. This value agrees well with the theoretical value of +2.489 n.m. obtained from shell model calculations using the GXPF1 interaction [2].

References:
1. J.S. Berryman et al. Phys. Rev. C, 79 064305 (2009).
2. T.E. Cocolios et al. Phys. Rev. C, 81 014314 (2010).

The dissemination of knowledge to the general public is fundamental to the modern University. Along with education and research publication, results of academic research can be used for societal benefit through commercialization. Intellectual property, especially patents, plays a key role in moving research from the lab into commercial products. Recently Congress passed the America Invents Act, changing some important aspects of US patent law. The particulars and process of obtaining patents is discussed and how patenting works at MSU is explained.

The U.S. Department of Energy responded to the Fukushima Dai-ichi nuclear emergency by deploying a technical team consisting of approximately 35 people and 17,000 lbs of equipment to Yokota Air Base outside of Tokyo. DOE retained a presence in Japan from mid-March until the end of May assessing the consequences of the release of radiation from the damaged plants and providing technical advice to U.S. and Japanese Government officials. This talk will provide background information on the missions and capabilities of the DOE Office of Emergency Response and describe our efforts in support of the Fukushima Dai-ichi crisis. In recognition of our work in Japan, DOE team members were recognized by Secretary Chu as recipients of the 2011 Secretary’s Achievement award for meritorious service to the Department and the Nation.

Double beta (2β) decay is an extremely rare form of decay that has only been observed in a handful of isotopes [1]. There are two possible mechanisms for double beta decay. The first is explained by known physics, and is identified as the two-neutrino mode, wherein a nucleus increases its proton number by two, and emits two electrons and antineutrinos. The second mode is neutrinoless double beta decay and is forbidden in the standard model [2]. Though the neutrinoless mode has never been observed, its observation would prove that neutrinos are Majorana leptons, i.e. that neutrinos are their own antiparticle [2]. Study of the two-neutrino mode remains the only observable measure of double beta decay and is important to investigate in its own right. Two neutrino decay can be used to study particle properties, investigate candidate 2β nuclei, and calculate theoretical parameters for the decay matrix elements for both modes [2,3]. Recent results from two experiments, NEMO-3 (Neutrino Ettore Majorana Observatory) and EXO-200 (Enriched Xenon Observatory) provide new results for Te-130 and Xe-136 [2,4]. In past geochemical measurements of Te-130, two conflicting values of the half-life were measured. NEMO-3 sought to reconcile this difference, and measured a half-life closer to the lower value, 7.0±0.9 x 10²⁰ yr, which is also the most precise measurement to date [4]. EXO-200 is the prototype for the larger scale EXO experiment and was the first experiment to directly observe the decay of Xe-136. The measured half-life was 2.11±0.04(stat)±0.21(syst) x 10²¹ yr, which is notable in that it is an order of magnitude lower than the previously set lower limits [2]. References: 1. A. S. Barabash, Phys. Atom. Nucl. 74, 603 (2011). 2. N. Ackerman et al., Phys. Rev. Lett. 107, 212501 (2011). 3. A. S. Barabash, Phys. Atom. Nucl. 73, 162 (2010). 4. R. Arnold et al., Phys. Rev. Lett. 107, 062504 (2011).

Fermilab intends to remain the best location in the world to perform experiments at the “Intensity Frontier”, by building an external beam of 0.7 MW or more. The primary focus is a study of muon neutrinos transforming to electron neutrinos (a measurement of ), leading to resolution of the neutrino mass hierarchy, and observation of CP-violation in leptons, a possible source of the matter-antimatter asymmetry of the universe. The NOvA experiment, constructing a 15-kT liquid-scintillator detector, is to begin a 6-yr run in 2013. A new technology, the Liquid Argon Time Projection Chamber (50-100 kT), is being developed for a future neutrino oscillation experiment and searches for proton decay. Contributions of MSU to these efforts will be highlighted.

Nuclear observables such as binding energies and cross sections can be directly measured. Other physically useful quantities, such as spectroscopic factors, are related to measured quantities by a convolution whose decomposition is not unique. I'll illustrate the possibilities, pitfalls, and open questions of such scheme-dependent observables for low-energy nuclear physics.

The two-neutron decay of neutron-unbound states has been one of the most exotic decay modes along the neutron drip line. The two neutrons can be emitted in two sequential decays or they can be emitted simultaneously. The simultaneous emission has been of great interest due to the possibility of a di-neutron emission, similar to a di-proton emission at the proton-dripline. A recent MoNA/Sweeper experiment revealed the first observation of ground state di-neutron decay in the nucleus 16Be. 16Be is bound with respect to the emission of one neutron and unbound to two-neutron emission. The di-neutron character of the decay was evidenced by the small relative angle between the two neutrons and by the sharp relative 2n-energy. The 2n-analysis of the 16Be decay will be presented and the results on the 2n-separation energy will be compared to shell model calculations.

Electric Dipole Moments (EDM) are a promising place to search for new sources of CP violation. The first search for a neutron EDM took place more than 60 years ago, with sensitivities improving nearly eight orders-of-magnitude up to today. New experiments and techniques for further improving the neutron EDM sensitivity will be discussed.

Exotic nuclei with very unusual proton-to-neutron ratios often show surprising phenomena, presenting important challenges to our understanding of atomic nuclei. The goal of present-day nuclear physics is thus to establish the unified understanding of nuclear structure for stable and exotic nuclei, by exploring the isospin degree-of-freedom of the shell structure and collective properties of nuclei. The present talk focuses on recent lifetime measurements at NSCL of neutron-rich and proton-rich nuclei in the vicinity of N = 40. The isotonic symmetry manifested in the shell quenching phenomena has been investigated through spectroscopic studies of exotic nuclei. The experimental results will be presented and discussed in terms of possible mechanisms responsible for the shell evolution along the N=40 line.

Jack Bass (with William P. Pratt Jr. and P.A. Schroeder) In 1988, A.Fert and P. Grunberg independently discovered Giant Magnetoresistance (GMR) in Current-in-Plane (CIP) measurements on Ferromagnetic/Non-magnetic (F/N) multilayers of antiferromagnetically coupled Fe/Cr. In 2006 they shared the Noble Prize for their discovery, for the wide-ranging physics and technologies (including both sensors and computer read-heads) to which it gave birth. I’ll argue that the alternative Current-Perpendicular-to-Plane (CPP) geometry, pioneered at MSU in 1991, is not only often larger than the CIP-MR, but obeys simpler equations, giving more direct access to the detailed physics underlying GMR. Over the past two decades, we have used unique experimental capabilities to determine, for a wide variety of both F/N and N1/N2 multilayers, the parameters that characterize both the individual layers and their interfaces. Only a few of these parameters (all within layers) were known from prior measurements of other kinds. We used those known parameters to help test and validate the models that we use to analyze our data. For the rest of the parameters (especially all of those for interfaces), essentially nothing was known when we began. I’ll describe how we determine such parameters and what we find. Of special interest are cases where we can now compare our derived parameters with calculations involving no adjustability.

ME/NSCL Seminar Series talk

In this talk I will discuss both finite and infinite systems. The physical settings will range from heavy nuclei, to neutron stars, and down to ultracold atomic gases. More specifically, I intend to talk about quantum many-body theory in various forms, most notably energy-density functionals and microscopic Monte Carlo simulations on modern supercomputers. Touching upon many theoretical methods, I will attempt to show the unifying thread: experimental evidence that constrains both terrestrial and astrophysical systems.

The Lead Radius Experiment (PREX) at Jefferson Laboratory uses parity violating electron scattering to measure the neutron radius of 208Pb. This electroweak reaction is free from most strong interaction uncertainties. We describe the experiment, present first results, and discuss some of the implications for nuclear structure and neutron rich matter in astrophysics. We end with possibilities for future measurements.

Renewed interest in the physics of nuclei is fueled by experiments at rare isotope beam facilities, which open the door to new regions of exotic nuclei; by astrophysical observations and simulations of neutron stars and supernovae, which require controlled extrapolations of the equation of state of nucleonic matter in density and isospin; and by studies of universal physics, which unite cold atom and dilute neutron physics. Progress on the nuclear many-body problem has long been hindered by the strong coupling between low- and high-energy states induced by typical nuclear Hamiltonians, which is manifested as highly correlated many-body wave functions and nonperturbative few and many-body systems. In this colloquium I describe how the interplay and coalescence of different threads: rapidly increasing computational power, effective field theory (EFT), and renormalization group (RG) transformations are enabling the development of new many-body methods and the revival of old ones to successfully attack these problems.

The nu-p-process is thought to occur in the innermost proton-rich layers ejected in core-collapse supernovae. The importance of the nu-p-process lies in the fact that it may contribute to the abundances of elements above nickel and possibly light p-nuclei. The reaction path of the nu-p-process lies in a region where nuclear masses are partly unknown and all involved reaction rates are based on theoretical predictions.I will report on a detailed study of the nu-p-process nucleosynthesis and its uncertainty due to nuclear physics, focusing on the reaction path at and above 56Ni. I will discuss how nuclear structure determines the basic properties of the process and how well it is constrained.

The Continuum Discretized Coupled Channels (CDCC) method is a well established theory for the direct nuclear reactions which includes breakup to all orders. In CDCC, the 3-body problem is solved by expanding the full wave function in terms of a complete basis of the projectile's bound and continuum states. Alternatively, the 3-body problem can be solved \exactly" within the Faddeev formalism which explicitly includes breakup and transfer channels to all orders. Thus with the aim to understand how the CDCC compares with the exact 3-body Faddeev formulation, we study scattering of deuterons for a variety of cases, including elastic, breakup and transfer processes. This comparison provides range of validtity for CDCC.

The ISAC accelerators presently deliver various stable and radioactive ion beams with widely varying beam energies and intensities. Monitoring of beams with currents lower than ~0.5 epA requires a dedicated diagnostics instrumentation which, typically, makes use of radiation tolerant single particle detectors. Several such devices have been built and are under development at TRIUMF. Device controls and data acquisition are integrated into the EPICS environment and provide standardized, simple and transparent operation. Details of the design, tests and beam measurements will be present.

The LEBIT (Low Energy Beam and Ion Trap) Penning trap mass spectrometry facility at the NSCL was the first to perform mass measurements on rare-isotopes produced via projectile fragmentation. Due to current upgrades to the NSCL’s gas stopping facility and the expansion of experimental programs that will utilize the low-energy beams they provide, LEBIT was temporarily decommissioned in 2009 and relocated to a new experimental vault. This period provided the opportunity to initiate development projects motivated to extend our scientific reach towards more exotic isotopes, i.e. shorter-lived and very low yield, increase efficiency and make more economic use of beam time, expand our off-line mass measurement capabilities, and increase precision for special cases. These developments include the implementation of the SWIFT (Stored Waveform Inverse Fourier Transform) technique to most effectively remove contaminant ions from the Penning trap, a miniature Penning trap for continuous magnetic field monitoring, a laser ablation source to provide reference ions and stable isotopes, and the development of a new Penning trap mass spectrometer with capabilities for performing mass measurements with single ions. The LEBIT system was recommissioned during 2011 with an off-line ion source and a campaign of mass measurements on isotopes of interest for neutrinoless double-beta-decay is underway. In this talk I will discuss the new developments at LEBIT. I will present the first measurements with the relocated LEBIT facility of the mass of 48Ca and discuss the implications for 48Ca double-beta-decay.

To understand why matter is stable, and thereby shed light on the limits of nuclear stability, is one of the overarching aims and intellectual challenges of basic research in nuclear physics. To relate the stability of matter to the underlying fundamental forces and particles of nature as manifested in nuclear matter, is central to present and planned rare isotope facilities. Important properties of nuclear systems which can reveal information about these topics are for example masses, and thereby binding energies, and density distributions of nuclei. These are quantities which convey important information on the shell structure of nuclei, with their pertinent magic numbers and shell closures or the eventual disappearance of the latter away from the valley of stability. Neutron-rich nuclei are particularly interesting for the above endeavor. As a particular chain of isotopes becomes more and more neutron rich, one reaches finally the limit of stability, the so-called dripline, where one additional neutron makes the next isotopes unstable with respect to the previous ones. The appearance or not of magic numbers and shell structures, the formation of neutron skins and halos can thence be probed via investigations of quantities like the binding energy or the charge radii and neutron rms radii of neutron-rich nuclei. In this talk I will present some recent calculations on properties of oxygen and calcium isotopes towards their corresponding driplines and point to new experiments. In particular I will focus on ground state properties and excited states, with an emphasis on the role of two- and three-body forces using first principles methods like coupled-cluster theory. I will also try to outline present and future challenges to nuclear many-body theory and how to understand the above properties in terms of the underlying forces.

The Large Binocular Telescope, with its two 8.4-m diameter primary mirrors, is instrumented to achieve angular resolution 3-10x sharper than that of Hubble Space Telescope. Problems uniquely well addressed by this facility include the epoch of reionization and the physical properties of the earliest galaxies, stellar populations in the local Universe and their indicators of the cosmic distance scale, the distribution of stellar mass and multiplicity in star forming regions, and the census of extrasolar planets. These discoveries are enabled by first-of-a-kind systems: adaptive optics with a 0.9-m deformable secondary mirror and pyramid wave front sensor, Fizeau interferometry with an extended field of view at maximum resolution, Rayleigh beacon laser guide stars that allow correction of ground-layer atmospheric turbulence, and complex cryogenic mechanism control for near-infrared multi-object spectroscopy. The efforts of integration and commissioning are just beginning to yield the scientific payoff expected from this 23-m prototype telescope.

While at the shortest distance scales, most of the sea of quark-antiquark pairs in the proton are the result of gluons splitting into quarks and antiquarks, there is clear evidence for a significant flavor asymmetric and non-perturbative sea, especially at momtentum fraction values around 0.1. This talk will review the evidence for the non-perturbative sea, the possible mechanisms that create it, and the experiments needed to understand its origin including the on-going SeaQuest experiment at FNAL.

The mechanism for converting carbon into oxygen in the universe is one of the most interesting and complex problems our scientific community faces now. I will tell the story of how the "Holy Grail" of nuclear astrophysics came to be. I will also discuss the various approaches being used over the years and planned in the near future across the globe to try to solve the problem. I will pay special attention to our latest bubble chamber results.

DAEdALUS is a concept for an experiment to measure the CP-violation angle in the neutrino sector by producing multiple, intense beams of neutrinos from pion decays at rest. The proton drivers will be high-power cyclotrons. The experiment would be located near an ultra-large water Cerenkov or scintillator detector. We propose a 4-Phase program of accelerator development that allows for interesting particle physics results at each stage. I will describe our ongoing research. I will especially highlight Phase II, an electron-neutrino disappearance search using an isotope-decay-at-rest beam produced by a 60 MeV/amu cyclotron that could run at KamLAND or another large scintillator detector in 2016.

Electron shake-off and shake-up are atomic processes in which a bound electron is excited into the continuum or in a new orbital, resulting from a sudden change of the central potential. Such a modification can for instance arise in nuclear beta decay so that those processes can adversely affect precision measurements at low energies. The probability for the shake-off and shake-up processes can be calculated in the framework of the sudden approximation but comparisons with experiments are usually difficult since secondary processes, like the emission of Auger electrons, can also be into play. In this talk I will describe the first measurement of a pure electron shake-off in the beta decay of a hydrogen-like system. The measurement uses trapped 6He+ ions which provide a unique case in which all conditions are met to compare, with high precision, the experimental result with simple calculations made in the sudden approximation.

Modern theoretical particle physics models are both elegant and powerful. These theories can predict precision measurements of fundamental interactions over many orders of magnitude, but they are intrinsically flawed. A major problem arises when one considers a seemingly trivial concept: the masses of elementary particles. Most particle physicists believe this issue is addressed by an electroweak symmetry breaking model known as the Higgs mechanism, which predicts the existence of a new (and unobserved!) particle, the Higgs boson. For nearly 50 years physicists have sought the Higgs boson, searching in dark corners for signs of its existence. After following trails of clues, the collider experiments at the Fermilab Tevatron and the CERN Large Hadron Collider may together be seeing the first tangible hints of the Higgs boson. This presentation will discuss the basic motivations for the Higgs mechanism and the exciting, new results on Higgs searches from the Tevatron and the LHC.

Recent developments in the detector fabrication, signal readout, and data processing enable new concepts in radiation detection that are relevant for applications ranging from fundamental physics to medicine and nuclear security. I will discuss some examples of our recent efforts on the development of ultra-low noise – so-called point-contact - detectors, three-dimensional position sensitive detectors to enable efficient gamma-ray imaging, and the fusion of gamma-ray and object information in 3 dimensions leading to the new concept of the Nuclear Street View. These technical developments will be mapped to applications in nuclear and astrophysics, the verification of ion-cancer therapy, nuclear safeguards and homeland security.

The acceleration of the Hubble expansion may be due to the failure of General Relativity to explain gravity on cosmological scales. This can be tested by measuring the gravitational growth of the largest structures, 100 Mpc or larger. The standard methods for such experiments involve measuring power spectra at different epochs, and are therefore limited by fluctuations from the finite number of large-scale modes in the observable Universe, a.k.a. "cosmic variance." I will describe how galaxy redshift and weak gravitational lensing surveys can be combined in a new way to measure gravitational growth to theoretically unlimited precision with a finite survey of the sky.

With the continued deployment of computational resources of increasing capability and capacity, the numerical technique of Lattice Quantum Chromodynamics (QCD) is moving toward becoming a practical tool with which to calculate the properties and interactions of strongly interacting particles such as the nucleons and hyperons. It will allow for the quantification of uncertainties in quantities of importance in nuclear physics, such as reaction rates and the composition of hadronic matter, and provide a reliable method with which to calculate processes that are inaccessible to experiment. I will discuss the progress that is being made toward achieving this objective.

Determining the nuclear equation of state has been one of the long-term goals of the nuclear reaction community. Currently, the term with the largest uncertainty is the symmetry energy, which describes the energy difference between isospin symmetric nuclear matter and pure neutron matter. The density dependence of the symmetry energy plays a role in many aspects of nuclear reactions, structure, and astrophysics, ranging from understanding the thickness of the neutron skins on heavy nuclei to the maximum mass and radius relationship of neutron stars. As the sign of the symmetry potential is opposite for protons and neutrons, one promising probe to study the symmetry energy is the differing spectra of protons and neutrons emitted from heavy ion collisions. Little data actually exists on this observable, however, due to the complexity of detecting neutron energy spectra. I will describe a recent experiment that measured proton and neutron spectra from Sn + Sn collisions at the NSCL. Preliminary results will be compared to theory and previous data, where available.

One of the first quantities that can be measured for newly discovered isotopes is their production cross section. The production cross section is important to plan for other experiments that might use a specific isotope as their object of study. It also can reveal nuclear structure changes over a range of isotopes. In my presentation I will outline a basic cross section measurement experiment and its analysis. I will focus on some of the details of how to extract the cross section based on the collected experimental data.

Effective field theory provides a systematic approach to interacting quantum systems at low energies and densities. Lattice effective field theory combines this approach with non-perturbative lattice methods. I discuss recent applications of lattice effective field theory to the physics of cold atomic superfluids, neutron matter, and nuclei with up to 20 nucleons.

In the first part of the talk I will give an overview of where we stand in the microscopic description of the Hoyle state in 12C in terms of three losely bound alpha particles. I will move on to identify an analogue to the Hoyle state in 16O. Heavier n alpha nuclei will be treated with the Gross-Pitaevskii equation. In the second part of the talk I will outline how to deal with alpha condensation in macroscopic systems as, e.g. in compact stars. I will point to eventual strong differences between pairing and quartetting.

What is the limit of the periodic table of the elements? The existence of super-heavy nuclei requires an incredibly delicate interplay between macroscopic liquid-drop energy and the extra binding associated with quantum shell corrections. Without these quantum effects, super-heavy nuclei would immediately decay due to the Coulomb repulsion between the large number of protons. I will describe a new generation of experiments, including preliminary results taken with the GRETINA array, on the structure and properties of the heaviest nuclei. These experiments are addressing the fundamental issue of the maximum mass and charge that a nucleus can attain. The results are testing predictions, stretching back more than forty years, of a possible "island of super-heavy stability". The talk will be accessible to students with an interest in nuclear science.

There are a wide variety of phenomena that are of interest in exotic nuclei such as clustering, evolution of structure, and the role of nuclei in nucleosynthesis. With the availability of new radioactive beams, such as from ReA3 in the near future, we will have access to a broader range of these rare nuclei. Developments in detector technology are needed to make full use of these radioactive beams, which come with challenges such as low beam rates. The Active-Target Time Projection Chamber (AT-TPC) is a new generation time projection chamber being developed for nuclear physics experiments with beams of exotic nuclei. Its main feature is its tracking chamber, which has the ability to track beam and reaction particles. This tracking feature allows the detector to have good energy and angular resolution as well as a large angular acceptance for reaction products. In this presentation, I will present an overview of the AT-TPC project and its current status including details of some the development projects that the group is currently involved in, which includes testing and simulation of components, target gases, and work with the half-scale Prototype AT-TPC. I will also mention some future plans envisioned for the Prototype detector.

We explore synchronization in networks of coupled nonlinear oscillators in our laboratory. Numerical models are developed and simulations are compared with experimental observations to understand how real networks synchronize and desynchronize as coupling coefficients are varied. Convergence to synchrony is found to depend on the network topology. Next, we report results of experiments on coupled map lattices with liquid crystal spatial light modulators and the observation of chimera-like states when nonlocal coupling is realized. The relevance of such states to neuronal networks will be discussed.

Projectile fragmentation has been used for decades to produce rare isotope beams for use in advancing nuclear science. Multiple observables are available for studying the underlying reaction mechanism including measurement of the linear momentum of final fragmentation products. Furthermore, the two components of the linear momentum, the parallel momentum distribution and the perpendicular momentum distribution, have been studied very disparately with more measurements of the parallel momentum distribution of fragmentation products.

The full parallel and perpendicular momentum distributions have been measured as a function of fragment mass loss for a wide range of fragments (A=37 to 75, Z=17 to 33) produced from interaction of a Ge-76 beam at 130 MeV/nucleon on either a Be-9 or Au-197 target. The parallel momentum distributions were found to be independent of target species and agree with both previous measured distributions and models of distribution width by Goldhaber and Morrissey. The perpendicular momentum distributions were found to agree with models of the distribution width by Van Bibber for fragments produced with the light beryllium target or fragments with a mass loss greater than 20 produced with the heavy gold target. The distribution widths of the heaviest fragments produced with the gold target had scattering angles that could be described by a calculation of the classical deflection function using a repulsive Coulomb plus an attractive nuclear scattering potential between the fragment and the gold target.

The particle identification procedure used with the S800 spectrometer at the National Superconducting Cyclotron Laboratory has been improved by the addition of the identification of the atomic charge-state of incoming particles. The total kinetic energy of incoming particles can now be measured with a new CsI(Na) hodoscope array, which has been characterized as a function of particle energy, mass, and nuclear charge. The energy resolution was deduced to be approximately 3% in the 100 GeV total kinetic energy regime.

The separation of the trivalent actinides from the trivalent lanthanides continues to be one of the more difficult problems in separation science. Interest in this problem is increasing as a result of the need for separation of americium and curium (minor actinides) from the lanthanide fission products for advanced reprocessing of used nuclear fuels. The successful separation of these elements would allow the minor actinides to be recycled for reactor fuel where they would be consumed and the remaining lanthanides could be disposed in a suitable waste form. Solvent extraction processes have been developed to accomplish this task and involve the tendency of the minor actinides to form stronger complexes than do lanthanides with soft donor atoms such as nitrogen and sulfur. A brief history of the separation of actinide elements will be presented along with current efforts to utilize soft donor atoms to develop an efficient and robust separation process.

U.S. physics education faces serious challenges: undergraduates and high school students are inadequately prepared, and there is a critical shortage of K-12 teachers. The Colorado Learning Assistant (LA) model helps address these intertwined problems: it provides an easy-to-adapt program that both enhances university-level science instruction and improves science teacher recruitment and preparation. I present evidence from discipline-based educational research that the Colorado Learning Assistant model positively impacts undergraduate student performance while at the same time significantly increases the number and quality of K12 teachers. It also engages research faculty in improving undergraduate instruction, including upper division, as well as in taking some responsibility for recruiting and preparing their majors for all careers, including K-12 science teaching. I will also discuss the recent report of the National Task Force for Teacher Education in Physics as well as give some information about the recent National Research Council’s Committee on Undergraduate Physics Education.

Charge-exchange reactions induced by radioactive heavy-ions have potentiality for studies of a variety of spin-isospin responses due to their unique reaction kinematics and selectivities. Among them the (12N,12C) reaction has peculiar features: This reaction can be exothermic (Q > 0) owing to the large mass difference of about 17 MeV between the 12N projectile and the 12C ejectile, and accordingly it can realize small momentum transfer even for highly-excited states. Moreover, since the final state in the 12C ejective can be identified by detecting the de-excitation gamma rays, the excitation modes with the transferred quantum numbers (S = 1, T = 1) and (S = 0, T = 1) can be selected. These features make this reaction suitable for the study of yet-to-be-discovered states such as the isovector spin monopole resonance (IVSMR). We performed for the first time an experiment of this exothermic charge-exchange (12N,12C) reaction on a 90Zr target at an incident energy of 175 MeV/u at the RI Beam Factory (RIBF) at RIKEN using the magnetic spectrometer SHARAQ and the gamma-ray detector array DALI2, and observed the isovector spin monopole strength in 90Nb. In this research discussion, I will present the details of the experiment and discuss the results.

The slight difference in the interactions of matter and anti-matter connotes CP violation. CP violation has been studied extensively in weak decays, and thus far, save for some tantalizing hints, all is consistent with the Standard Model. However, our inability to explain the baryon excess we observe in the universe suggests that additional sources of CP violation must exist, though experiment tells us that these sources appear to be associated with energy scales currently beyond our reach. In this context improved limits on processes which are highly forbidden in the Standard Model, such as the permanent electric dipole moments of ground-state particles or certain, rare decay observables, bound new sources of CP violation. In this talk I discuss the possibility of using a triple momentum correlation in the radiative beta-decay of neutrons and nuclei as a new probe of CP-violating effects.

The unique radioactive ion beams available at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory were used to study fusion reactions near and below the Coulomb barrier. Two open questions regarding heavy-ion fusion were addressed: (1) What is the role of transfer coupling in heavy-ion fusion? A number of previous studies have shown large enhancements in the sub-barrier fusion cross sections in correlation with the presence of positive Q-value neutron transfer channels. The fusion excitation functions of 132Sn+58,64Ni were measured and compared with stable Sn+Ni measurements. While the number of positive Q-value neutron transfer channels varied widely between the different Sn+Ni systems, the reduced excitation functions were equivalent. This suggests a significant change in the influence of transfer couplings on the Sn+Ni fusion process. (2) How does quasi-fission or fusion hindrance change as a function of isospin? The presence of quasi-fission in near-barrier reactions can hinder fusion by orders of magnitude. Experiments examining quasi-fission as a function of the neutron-richness of the reaction system have presented conflicting results. Through measuring the evaporation residue cross section for different radioactive Sn+Ni systems the fusion hindrance was estimated. The results indicate that the fusion hindrance does not increase with increasing neutron-richness.

Our picture of neutrinos has changed dramatically over the past ten or fifteen years, and our physics goals for neutrino measurements have likewise evolved. In this talk, I will discuss some of the outstanding questions in neutrino physics, and present the status and plans of the SNO+ experiment. SNO+ will replace the heavy water used by the Sudbury Neutrino SNO+ Observatory (SNO) with liquid scintillator, and in so doing will allow us to explore some of the most compelling of these remaining questions about neutrinos.

Recently, the MoNA collaboration has begun exploring nuclei which lay two neutrons beyond the neutron dripline. The ground-state resonances of these two-neutron unbound nuclei can be measured through the 3-body coincidence detection of the fragment+n+n systems using the MoNA-Sweeper setup. Experimental results for the observations of the two-neutron unbound 26O, 16Be, 13Li and 10He nuclei will be presented. These nuclei were populated through single proton-knockout reactions from radioactive ion beams produced at the National Superconducting Cyclotron Laboratory. The implications of the measured ground state energies of each nucleus will be discussed. Additionally, the 3-body correlations were examined from the 16Be and 13Li systems and showed strong dineutron characteristics.

The Pygmy Dipole Resonance (PDR) is a mode of nuclear excitation appearing at large neutron-to-proton imbalances in medium to heavy mass nuclei. Macroscopically, the PDR can be considered as an isospin-symmetric core oscillating against a shell of the remaining excess nucleons, in contrast to the well known Giant Dipole Resonance (GDR), in which the entire proton and neutron distributions oscillate against each other. Since the existence of this low-lying dipole mode is related to the neutron-proton asymmetry, the systematic investigation of the PDR contributes to the understanding of the nuclear equation-of-state. Several experiments have been carried out in the past years using the R3B-LAND setup at GSI in Darmstadt, in which the electric dipole strength of exotic nuclei has been studied. The experimental method was based on heavy-ion-induced electromagnetic excitation and the subsequent particle and photon decay. Preliminary E1 strength distributions will be presented for neutron-rich Ni isotopes. In particular, the differential cross sections for the neutron-decay channels of 68Ni will be compared to other experimental data, obtained by virtual photon scattering. Preliminary data on the proton-decay channels of 32Ar and 34Ar will also be presented, for which a proton-related PDR has been predicted by an RPA calculation.

Moving away from the valley of beta-stability and towards the driplines, it is understood that the position and robustness of the ‘magic numbers’ is modified by the residual nucleon-nucleon interaction. Such modifications can result in dramatic changes in the structure of the most exotic nuclei. In N=40 nuclei below Z=28, for example, the tensor monopole component of the effective nucleon-nucleon interaction results in a weakened sub-shell gap and the onset of quadrupole collectivity in neutron-rich Cr and Fe isotopes. First evidence for a weakening of the N=40 shell gap, and onset of quadrupole collectivity has been observed in the Cr and Fe isotopes as a steady decrease of the 2+ energies through N=40. Excited state lifetime measurements have confirmed collectivity in the Fe isotopes up to N=40, and added to mounting evidence for a new “island of inversion” centered near ¬64Cr. At lighter masses, the weakening of the N=28 shell closure in neutron-rich nuclei also leads to significant changes, inducing changes to the nuclear shape. The collapse of this shell closure leads to a large prolate deformation in 44S, and has suggested a large oblate deformation in 42Si at Z=14 and N=28. The isotonic nucleus 40Mg may be expected to have “mid-shell” character, and a similarly large deformation. We have recently studied the evolution of nuclear shell structure in the regions around 64Cr and 40Mg. The collectivity of 66,68Fe isotopes and 64Cr has been studied via intermediate-energy Coulomb excitation at NSCL using the S800 spectrograph and the scintillator array CAESAR. Preliminary results for the B(E2) of 66, 68Fe and 64Cr will be presented, and discussed in terms of the evolution of collectivity near Z=24 and N=40. In the neutron-rich N=28 isotones, the inclusive two-proton knockout reaction cross-section for 42Si into 40Mg has been measured in an experiment performed at the RI Beam Factory, at RIKEN Nishina Center. New cross-section results, and the systematic evolution of nuclear structure along the N=28 isotonic chain will be presented and discussed.

Heavy elements are produced at the rate of events per second down to events per month or year at high intensity, stable beam facilities. The facilities geared towards understanding the production and decay of these elements require high beam intensities on the order of 1013 particles per second and instrumentation or techniques capable of separating the product of interest from the beam and unwanted reaction products. The commissioning and improvement of such instrumentation is vital for increasing experimental sensitivity and pushing towards products with heavier Z. Here I will present i) the first heavy element experiments at the recently commissioned gas-filled separator TASCA ii) the subsequent efforts to understand particle trajectories of products of interest, beam and unwanted reaction products in TASCA in preparation for on-going experiments devoted to the discovery of elements 119 and 120 and iii) development of upgrades to the Berkeley Gas-filled Separator (BGS) that couple the BGS to a mass analyzer to allow for transportation of mass-separated nuclear reaction products to a shielded detector station on the tens of milliseconds timescale.

Abstract: RMT gives descriptions of the spectra of chaotic systems. One can compare the level spacing distribution and the so called $\Delta_3$ statistic with the results of RMT and get estimates of missed levels and intruder levels. In this talk a brief overview of RMT, and a thorough description of the $\Delta_3$ statistic, both aimed at the novice, will be given. Then a maximum likelihood method based on the $\Delta_3$ statistic will be described and applied to neutron resonance data and acoustic spectra of aluminum blocks. Time permitting, 2 additional problems will be described. The distribution of widths in a model of an open quantum system, and a general randomly-interacting boson model.

The Daya Bay Reactor Neutrino Experiment is designed to be the most sensitive one to measure sin22θ13 among the current generation of short-baseline reactor neutrino experiments. Located in Southern China, its eight functionally identical detectors are hosted in the three underground experimental halls on the campus of the Daya Bay nuclear power plant where six 2.9GWth pressure water reactors provide copious electron antineutrinos. With eight weeks of data taken by the first six detectors which were commissioned by Christmas 2011, Daya Bay announced a 5-sigma discovery of non-zero θ13 on Mar 8, 2012. Additional data taken to mid-May 2012 has increased the signal significance to greater than 7-sigma, sin22θ13=0.089±0.010(stat)±0.005(syst). Daya Bay is currently completing its last two of the eight detectors and will commission the complete experiment in Fall 2012. Such an unexpected large sin22θ13 has encouraged studies of the potential to resolve mass hierarchy in a few under-construction and proposed experiments including Daya Bay II. In this talk, I will concentrate on the Daya Bay experiment design, installation, commissioning and data analysis. In addition, together with updates on the current status of Daya Bay, I will also give a brief introduction to some potential future developments relevant to the Daya Bay experiment.

The past fifteen years have seen a revolution in our understanding of the properties of the neutrino. A large set of experiments has observed two oscillation modes, indicating that there are three distinct mass states. In the last year, a third oscillation mode has been discovered, opening up future probes of new phenomena including CP violation. Despite the recent progress, however, much remains unknown about neutrinos and several experimental results remain difficult to reconcile with the simplest models. This talk will give an overview of what is known, what we're learning in this exciting era of measurements, and what we may be able to learn in the next decade and beyond.

Magic nuclei are cornerstones of nuclear structure. Due to the presence of large shell gaps between occupied and valence shells, they are spherical, have large excitation energies and weak excitation probabilities. They are often more abundant than other nuclei in the universe, play key roles in explosive nucleosynthesis, and could bind superheavy nuclei despite the large repulsive coulomb interaction. Our vision of immutable magic numbers, whatever the proton to neutron ratio, has been drastically changed these last years. In particular it has been demonstrated that the neutron magic numbers 8, 20 and 28 were vanishing far from stability. In parallel new magic numbers appear as N=16. These discoveries arose with the advent of radioactive ion beam facilities worldwide as well as progresses in detection systems. They pose fundamental questions such as: which parts of the nuclear force drive these modifications of shell closures? Are such effects observed throughout the chart of nuclides, or are they limited to medium mass nuclei? To which extent nuclear forces are changing when approaching the drip line ? What are the consequences of these shell modifications for explosive nucleosynthesis, and for the existence of superheavy nuclei? The present talk will present recent experimental studies performed at GANIL using transfer (d,p) reactions, and the combination of beta-decay and isomeric studies. The obtained results on the 69Ni, 34,35Si and 26F nuclei aim at addressing three important aspects of the nuclear force such as the three body force, the spin-orbit interaction and the behavior of nuclear forces at drip line, respectively. Tentative results and interpretations will be proposed.

Ultrafast science crossed the 1-femtosecond barrier just over one decade ago. In making this transition, we left perturbative nonlinear optics behind. The new world of extreme nonlinear optics is understood by following the semi-classical sub-cycle response of materials. In fact, attosecond pulse generation can be intuitively understood with only classical physics. However, at the atomic level, quantum mechanics can never be completely ignored. I will show how a quantum description of attosecond pulse generation map onto an interferometer – an electron interferometer created by light. A weak additional field can perturb the interferometer while simultaneously constructing a perturbative nonlinear optics on top of the extreme process. This leads to new spectroscopic methods for studying atoms and molecules and the only method for measuring the space-time structure of an attosecond pulse.

I will discuss the odd-even oscillations in the nuclear binding energies in terms the quantity D = BE(A+1) - BE(A-1) - 2 BE(A) as a function of neutron or proton number. Features of the experimental data will be related to pairing and shell gaps. Theoretical results with schematic and realistic models of the nucleon-nucleon effective interactions will shown. Data and theory will focus on results for the calcium isotopes, but the systematics of all known data will be discussed, including those based on recent data for the masses of 26O, 52Ca and 134Sn.

The structure and role of the Office of Science and Technology Policy is described. An overview of the FY2013 federal investments in science and technology is provided as well as a description of a few recent science and technology initiatives.

The fast two-nucleon removal (knockout) reaction was initially likened to 'hitting two birds with one stone'. The reaction, a regularly-used production mechanism for exotic species at the NSCL, has observables with sensitivity to the states of the nucleons near the Fermi-surfaces of the projectile, and thus has spectroscopic value. The modelling of the direct reaction mechanism and its degree of sensitivity to nucleon structures - that induce two-nucleon spatial correlations - will be discussed. Results, recent and future tests of the reaction mechanism predictions, and the sensitivity of observables to ab-initio structure model input in removal reactions from carbon-12 will be reviewed.

Transiting planets are special. The amount of light blocked by the planet as it passes in front of its host star sets the size of the planet (relative to the star). If an orbit can be derived from Doppler spectroscopy of the host star, the light curve also provides the orientation of the orbit, leading to the mass of the planet (again relative to the star). The resulting density for the planet can be used to constrain models for its structure and bulk properties. We are on the verge of using these techniques to characterize a population of Super Earths, planets in the range 1 to 10 Earth masses that may prove to be rocky or water worlds. Space missions such as Kepler, Plato, and TESS promise to play key roles in the discovery and characterization of Super Earths. Transiting planets also provide remarkable opportunities for spectroscopy of planetary atmospheres: transmission spectra during transit events and thermal emission throughout the orbit, calibrated during secondary eclipse. Spectroscopy of Super Earths will not be easy, but is not out of the question for the James Webb Space Telescope or the next generation of giant ground-based telescopes. Our long-range vision is to attack big questions, such as "Does the diversity of planetary environments map onto a diversity of biochemistries, or is there only one chemistry for life?" A giant first step would be to study the diversity of global geochemistries on super-Earths and Earth analogs.

Neutron-rich nuclei become increasingly sensitive to three-nucleon forces. These components of nuclear forces are at the forefront of theoretical developments based on effective field theories of quantum chromodynamics. I will discuss our understanding of three-nucleon forces and their impact on exotic nuclei, and show how new measurements constrain three-nucleon forces, and how this in turn constrains our knowledge of neutron-rich matter in neutron stars and other extreme astrophysical environments. Three-nucleon forces therefore provide an exciting link between the theoretical, experimental and observational nuclear physics frontiers.

Projectile fragments can be thermalized in buffer gas to supply rare ions to low energy experiments. I will present studies of "ion surfing" [1], a new method for transporting ions through gas-filled devices that use a RF gradient to repel the ions from the walls. Instead of relying on a fixed potential gradient to guide the thermal ions through the length of the cell, the ions are transported by a traveling wave superimposed on the RF field. The travelling wave is formed by an oscillating sinusoidal field applied to repeating sets of four electrodes. The field on each subsequent electrode is offset by 90 degrees in phase. Transport efficiency and velocity measurements were performed for rubidium and potassium ions over a wide range of conditions. With the optimal parameters currently attainable, >90% efficient transport over 10 cm at 80 mbar was observed for Rb and K ions with max velocities of 75 m/s and 50 m/s, respectively. The measurements were conducted in preparation for the cyclotron gas cell at NSCL. I will present the results of the latest measurements and comparisons to detailed simulations. [1] G. Bollen, Int. J. Mass Spect. 299, 131 (2011)

Information theory is a statistical theory dealing with the relative state of detectors and physical systems. Because of this physicality of information, the classical framework of Shannon needs to be extended to deal with quantum detectors, perhaps moving at relativistic speeds, or even within curved space-time. Considerable progress toward such a relativistic theory of quantum information has been achieved in the last fifteen years, while much is still not understood. This talk recapitulates some milestones along this road, and speculates about future ones.

Although known to us for over 60 years, pions and muons still harbor key questions concerning details of their properties that have not been fully answered. These questions have come into focus as particle and nuclear physics confront all available experimental results with detailed calculations of the Standard Model, and seek to find evidence of processes beyond the SM. The precision frontier at low energies thus provides complementary information to that collected at current high-energy colliders. The seminar will discuss recent and forthcoming results of a program of measurements of rare pion and muon decays at PSI.

The TTF3-style coupler is typically used to power 1.3 GHz TESLA-type superconducting cavities. For the US ILC program, parts purchased in industry for such couplers are received at SLAC where they are inspected, cleaned, assembled as pairs in a Class 10 cleanroom, pumped down, baked at 150 C and rf processed. The pairs are then shipped to FNAL and installed in cavities that are tested at input power levels up to 300 kW. The discussion will include lessons learned from preparation of 44 couplers for ILC at SLAC and infrastructure requirements.

Unité Mixte de Physique CNRS/Thales, Palaiseau, and Université Paris-Sud, Orsay, France Spintronics is often defined as a new type of electronics harnessing not only the charge of the electron but also its spin. Its development was kicked off in 1988 by the discovery of the Giant Magnetoresistance of the magnetic multilayers, a phenomenon that we currently use to read the hard disc of our computer. Nowadays spintronics has become a broad field of research expanding in many promising directions. After an introduction on the fundamentals of spintronics, I will review the developments of today and the perspective of applications. I will mainly focus on three topics: 1) Microwave generation by spin transfer, a field of research with fast recent advances anticipating applications shortly in telecommunications. 2) Spintronics with graphene and carbon nanotubes, an extremely promising direction to extend the limits of electronics with semiconductors (the “beyond CMOS” perspective). 3) Oxitronics: I will present works on devices based on magnetic, ferroelectric and multiferroic oxides and describe applications like ferroelectric memories and neuromimetic components.

The National Synchrotron Light Source-II (NSLS-II) is a new light source under construction at Brookhaven National Laboratory (BNL). Up to seven quadrupoles and sextupoles in the NSLS-II storage ring will be mounted on a common girder (~4-5 m long). These magnets must be aligned precisely to each other. The vibrating wire technique, first developed at Cornell, is being used to align the multipoles with a targeted precision of ±10 microns, well within the required tolerance of ±30 microns for the finally installed girder in the ring. Extensive R&D was carried out earlier to study sources of measurement errors and to improve accuracy. A fully automated system is now in use for production measurements and 76 assembled girders have been measured and aligned so far out of a total of 90 multipole girders. The R&D work that led to successful use of the vibrating wire technique, and the results obtained so far will be presented.

The continuous electron beam accelerator facility at Jefferson Lab, built with novel superconducting radiofrequency (SRF) technology, provides opportunities to discover fundamental new aspects of the structure of visible matter – protons, neutrons and other bound states, and of the strong interaction, described by the gauge theory Quantum Chromodynamics. Jefferson Lab’s accelerator, in operation since 1995, is unique in the world and is currently undergoing a major upgrade to double its energy. The upgrade will bring new opportunities, not only in the study of hadronic matter, but also in searches for new physics, such as a suite of experiments to search for massive “dark photons”. The powerful SRF technology also enables a new generation of facilities in nuclear physics, particle physics, and applied sciences. In this talk, I will give an overview of Jefferson Lab’s current and future science program, including an outlook for the future of the laboratory.

The cosmic microwave background (CMB) radiation reports the initial conditions in the universe for the formation of large scale structures (galaxies and their dark matter halos, clusters of galaxies). The rich angular power spectrum of the CMB's intensity, combined with measurements of the universe's expansion rate with supernovae, provides a remarkably explicit picture of the large scale dynamics and contents of the universe. Until recently, the most sensitive measurements of the CMB power spectra have only probed angular scales > 1/3 degree. Now, two special-purpose large telescopes, ACT and SPT, have produced maps of the CMB with 15x better resolution. The next step is for each to produce even more sensitive maps with polarization-sensitive receivers. At such small angular scales, the CMB carries additional information about conditions at the epoch of last scattering (Neff, Yp) and before (r, ns, dns/dlnk), as well as information about the evolution of the structure in the universe which can answer questions on topics as diverse as the nature of the dark energy and the sum of the neutrino masses. I will provide a snapshot of the latest results, with an emphasis on ACT.

Superheavy elements represent a large extension (44% in atomic number Z) beyond lead, the last stable element. They occur only because a shell-correction energy provides extra binding, thereby creating a fission barrier, where none would otherwise exist. The shell energy arises from gaps in the single-particle energies. Therefore, the essential properties of superheavy nuclei are: the magnitude of the fission barrier, shell energy and single-particle spectrum. This talk will present results on these core properties. For these heavy nuclei the cross sections are miniscule, but it is now possible to study them at three simultaneous limits: in Z, spin and excitation energy. High-spin properties provide not only additional insight and tests of theory, but are also important because superheavy nuclei are formed at large angular momentum.

Halo nuclei are loosely bound nuclei whereby a few valence nucleons spend most of their time in a classically forbidden region, well beyond the range of the nuclear interaction. This phenomena has intrigued researchers for nearly two decades and new examples continue to appear. Halo nuclei have often been studied through breakup reactions which require reliable reaction theory for a meaningful interpretation. Although significant progress has been made on the reaction theory for breakup, calculated observables can still be strongly ambiguous due to uncertainties in the effective interactions. The ratio method, which we recently proposed, removes to a large degree the ambiguities and provides a very nice probe to halo structure.

Nuclear charge-exchange reactions, in which isospin is transferred between projectile and target nuclei, are a unique tool for extracting information about the spin-isospin response of nuclear matter. A surprising and particular interesting feature of nuclear charge-exchange reactions, which are mediated by the strong nuclear force, is that one can learn about properties of transitions mediated by the weak nuclear force that are not experimentally accessible in a direct way, for example via -decay experiments. These properties have important applications, in particular for the estimation of electron-capture rates during the evolution of stars just prior to their demise as thermonuclear or core-collapse supernovae, or in constraining theories necessary for extracting the effective Majorana neutrino-mass if discovery experiments for neutrinoless double beta decay are successful. Although charge-exchange reactions have been used intensively for a wide variety of purposes for more than 2 decades, in recent years new opportunities have become available because methods to perform these experiments with unstable nuclei were developed. This is important for the astrophysical applications since a large fraction of nuclei that play a role in late stellar evolution are unstable. In addition, such experiments open unique avenues to learn about the microscopic and macroscopic properties of nuclei and nuclear matter.

The region around N = 40 below Ni is currently an active area both experimentally and theoretically in an attempt to understand the rapid development of collectivity below ⁶⁸Ni as protons are removed from the f_7/2 single-particle state. The dramatic drop in the energy of the first excited 2⁺ states and increase in the B(E2) values along the Fe and Cr isotopic chains has been well documented. To further explore this region, the low-energy level structures of the neutron-rich Co, Mn and Fe isotopes were studied through beta-decay. The interpretation of the experimental data suggests the importance of proton and neutron excitations across the Z = 28 and N = 40 gaps, respectively. Results from selected nuclei near N = 40 will be presented along with an outlook for future investigations.

The Large Hadron Collider is now exploring the energy frontier of particle physics, searching for new particles and interactions. For the LHC to uncover many types of new physics, the "old physics" produced by the Standard Model must be understood very well. For decades the central theoretical tool for this job was the Feynman diagram. However, Feynman diagrams are just too slow, even on fast computers, to allow adequate precision for complicated events with many jets of hadrons in the final state. Such events are produced copiously at the LHC, and constitute formidable backgrounds to many searches for new physics. Over the past few years, alternative methods to Feynman diagrams have come to fruition. The new "on-shell" methods are based on the old principle of unitarity. They can be much more efficient because they exploit the underlying simplicity of scattering amplitudes, and recycle lower-loop information. Farther afield, the new methods have led to intriguing new results in quantum gravity. I'll explain how and why these methods work, and present recent state-of-the-art results obtained with them.

The importance of the nuclear inputs for r-process calculation and the astrophysical condition constraints have been demonstrated by reproducing the r-process abundance around A=135 and 180 with the neutron-rich nuclear masses around N = 82 and 126 predicted by FRDM and WS* models as well as the observed r-process abundance peaks at A = 80, 130, and 195. During the last decades, the covariant density functional theory (CDFT) with a minimal number of parameters allows a very successful description of nuclear ground state as well as excited state properties all over the nuclear chart. In this talk, exotic phenomena predicted by CDFT including the halos in deformed nucleus in the deformed relativistic Hartree-Bogoliubov theory in continuum, the crucial test for CDFT with new and accurate large-scale mass measurements from Sn to Pa, the beta-decay half-lives for 20  Z  50 even-even neutron-rich nuclei in the fully self-consistent proton-neutron quasiparticle random phase approximation based on the relativistic Hartree-Fock-Bogoliubov theory, and the speeding-up of the r-matter flow with the beta-decay half-lives of the neutron-rich nuclei thus obtained, will be briefly reviewed.

I will provide an overview of phases of matter at high density, their transport properties, and its relation to observable aspects of neutron star birth and evolution. The transport of heat and oscillation mode frequencies of the solid and superfluid phase of matter in the inner crust may be relevant for interpreting recent observations of accreting and magnetized neutron stars. I will describe in more detail a low-energy theory to calculate these properties and highlight the role of superfluidity and nuclear interactions. If time permits, I will also discuss very early (pro to-neutron star) and late time cooling of isolated neutron stars and the physics of high-density matter that plays a role.

The population of high-spin metastable excited states in heavy nuclei has been measured following fragmentation of uranium-238 ions at relativistic energies. The fraction of nuclei populated in an isomeric state with angular momentum > 18 hbar is underestimated by theoretical predictions by up to an order of magnitude. The enhanced isomeric beam yield reported here can be exploited in future experiments.

The goal of nuclear structure physics is a comprehensive understanding of the properties of nuclei and nuclear matter from the interactions of the constituent protons and neutrons. Enormous progress has been made with measurements of properties of rare isotopes and developments in nuclear theory. Typically, the most exotic nuclei provide the most stringent guidance for nuclear models and allow identifying “missing physics”. At NSCL, rare isotopes are efficiently produced by the in-flight fragmentation of stable beams and are available for measurements as beams of fast ions. Well-established experimental techniques used for decades to study stable nuclei are not applicable at the low beam rates encountered for the most exotic isotopes. Powerful new precision techniques have been developed to enable in-beam spectroscopy studies of fast rare-isotope beams with intensities of a few ions per second. This presentation will show how in-beam experiments measure complementary observables that advance our understanding of the structure of nuclei. The interplay of experimental results and theory will be emphasized at the intersection of nuclear structure and reactions in the joined quest for a reliable model of the atomic nucleus.

In the two-body final state of a gamma decay, photons have the same momentum as the recoiling nucleus. This would produce a single peak at P = E/c in the recoiling momentum spectrum of the nucleus. On the other hand, if massive particles are emitted in nuclear transitions instead of gamma photons, the recoiling nucleus will have a lower momentum than E/c. Measuring the recoiling momentum of the decay daughters allows us to indirectly search for any massive particle emitted in nuclear transitions, independent of particles¡¯ lifetime or their interactions in any detector. In this talk, I will present the experimental tests of searching for exotic particle emissions in the decay of laser-trapped 86Rb isomers (6- to 2- transition) by measuring the recoiling momentum of the decay daughters in a COLTRIM setup. I will discuss the experimental setups, photoionization schemes, the achieved 3% momentum resolution and the 10% sensitivity to exotic particle emissions. The photoionization scheme is a two-stepwise procedure, including the Doppler-free two-photon transition from the 5S_1/2 to the 5D_5/2 states by a 778 nm laser, and from the 5D_5/2 state into the continuum by a 1064 nm laser. By analyzing the measured 5S_1/2 to 5D_5/2 two-photon transition spectra, we deduced the related isotope shifts and hyperfine constants in radioactive Rb isotopes. The precision we achieved in the isotope shift measurements allows us to deduce the specific mass shifts between the 5S_1/2 to 5D_5/2 states with 4 - 28 MHz precision.

Two multi-nucleon transfer reactions were studied using a 6He beam on a 12C target with the Silicon Highly-segmented Array for Reactions and Coulex (SHARC), a compact charged particle silicon array, and the TRIUMF-ISAC Gamma-Ray Escape Suppressed Spectrometer (TIGRESS), a high-efficiency γ-ray detector, at the TRIUMF/ISAC-II facility. First, the reaction mechanisms of the (6He,4He) twoneutron transfer were studied to determine the dominant mechanism; the one-step simultaneous transfer or the two-step sequential transfer of two-neutrons. Second, the multi-nucleon transfer (6He,8Be) was observed and its reaction mechanism could proceed two ways, by a two-proton transfer or an alpha transfer. The two-neutron and multi-nucleon transfer reactions were analyzed and angular distributions extracted. These angular distributions were then compared to microscopic models investigating the effects of the simultaneous vs. sequential transfer mechanisms. Detailed simulations in GEANT4 were performed of the SHARC array to characterize detector performance. This presentation will discuss the experimental challenges, the results of the data analysis, GEANT4 reaction simulations and interpretation of the results.

I discuss the nuclear reactions/mechanisms used in the synthesis of the heaviest nuclei. For complete fusion reactions, involving stable or radioactive beams, the cross section for producing a heavy reaction product, EVR, can be represented as where capture(Ec.m., J) is the cross section at center of mass energy Ec.m. and spin J. PCN is the probability that the projectile-target system will evolve from the contact configuration to inside the fission saddle point to form a completely fused system rather than re-separating (quasifission, fast fission). Wsur is the probability that the completely fused system will de-excite by neutron emission rather than fission. I discuss the results of recent experiments that characterize these quantities in heavy element synthesis reactions. I point out the opportunities afforded by radioactive beams in heavy element synthesis, as well as the use of damped collisions and multi-nucleon transfer reactions.

The challenges of predicting and understanding nuclear properties, particularly of very neutron-rich and short lived isotopes, remains one of the pillars of the field of nuclear physics. Some of these short-lived isotopes can be produced in the laboratory, and are also produced during supernova explosions and other stellar events. Furthermore, certain nuclei have proven extremely beneficial for a variety of applications. During this talk, I will survey where the field of nuclear physics is today through recent experimental examples, and project where the field may go in the next 5-10 years. I will also discuss the role of theory in describing the physics of nuclei and recent developments of nuclear coupled cluster theory. I will also touch on the exciting opportunities afforded by coupling quantum many-body efforts to high-performance computing to enable descriptions of exotic nuclei.

Beta decay transitions between mirror nuclei, so-caled "mirror transitions", offer a sensitive window to study the structure and symmetries of the weak interaction. Data from mirror transitions have enabled the determination of standard model parameters, such as Vud element of the quark mixing matrix and provide also a mean to search for physics beyond the standard model. The sensitivity of mirror transitions is possibly best recognized in the decay of the free neutron but has otherwise not received particular attention in heavier nuclei. In this presentaion I will discuss the role of correlation measurements in mirror transitions for both, the determination of standard model parameters and tyhe search for new physics. The emphasis will be given on correlation measurements involving spin observables that require polarized low energy beams.

Type I X-ray bursts (XRBs) are thermonuclear explosions that occur in binary systems consisting of a neutron star accreting hydrogen-rich matter onto its surface from a main sequence companion star. Nucleosynthesis in XRBs is driven up the proton-rich side of the chart of nuclides by the rp and α, p processes to the SnSbTe region. Several intermediate mass nuclei, 22Mg, 26Si, 30S, and 34Ar, have been identified as possible candidates for waiting points in this α,p process. When such a nucleus is reached, the flow stalls due to a (p, γ)-(γ, p) equilibrium and must await β decay unless the (α, p) reaction is fast enough to break out of the waiting point first. Therefore, these waiting points may have significant effects on the final elemental abundances, energy output and luminosity profiles of XRBs. These α, p-process reactions have been studied via the time-inverse (p, α) reactions in inverse kinematics using radioactive ion beams produced by the in-flight method at the Argonne National Laboratory ATLAS facility. The results and possible implications for nucleosynthesis in XRBs will be discussed. This work was supported under JINA NSF grant No. PHY0822648 and U.S. DOE contract DE-AC02-06CH11357.

The nuclear symmetry energy affects many different aspects of nuclear structure, astrophysics and reactions. The spectral ratio of neutrons to protons from central heavy ion collisions is an observable that is sensitive to the symmetry energy at subsaturation densities, but is difficult to measure experimentally. A similar ratio using the mirror nuclei t/3He should display a similar sensitivity to the symmetry energy. Results of t/3He ratios from symmetric collisions of 112,124Sn+112,124Sn at E=50 and 120 MeV/nucleon will be discussed. These results will also be compared to theoretical predictions in order to constrain the density dependence of the symmetry energy.

During the helium burning phase of stellar nucleosynthesis, the production of ¹²C proceeds via a two-step process called the triple alpha reaction. In this reaction, two alpha particles react to form ⁸Be which is followed by the capture of a third alpha particle onto ⁸Be forming ¹²C. The second step of this reaction is enhanced by a narrow resonance with a 7.65 MeV 0+ state in ¹²C, the Hoyle state. The production rate of ¹²C is sensitive to the properties of the Hoyle state [1-4]. The work of Ref. [1] suggested the decay of Hoyle state proceeds almost exclusively through a sequential ⁸Be_g.s. + α channel and placed an upper limit of 4% on the contribution of the direct decay to three alpha particles [1]. Recent controversial results of the decay properties of the Hoyle state identify two new exotic direct three alpha decay modes with a combined decay branch of 17%, which implies a decrease of 17% in the production rate of ¹²C at temperatures of 10⁸ to 10⁹ K [2]. Subsequent studies attempting to resolve the apparent discrepancy between the previous investigations support the findings of Ref. [1] and find little evidence of the two newly proposed direct three alpha decay modes [3,4]. The experimental details and results will be presented along with conclusions regarding the Hoyle state decay controversy.

References:
1. M. Freer et al., Phys. Rev. C 49 R1751 (1994)
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In the two-body final state of a gamma decay, photons have the same momentum as the recoiling nucleus. This would produce a single peak at P = E/c in the recoiling momentum spectrum of the nucleus. On the other hand, if massive particles are emitted in nuclear transitions instead of gamma photons, the recoiling nucleus will have a lower momentum than E/c. Measuring the recoiling momentum of the decay daughters allows us to indirectly search for any massive particle emitted in nuclear transitions, independent of particles' lifetime or their interactions in any detector.

In this talk, I will present the experimental tests of searching for exotic particle emissions in the decay of laser-trapped ⁸⁶Rb isomers (6^- to 2^- transition) by measuring the recoiling momentum of the decay daughters in a COLTRIM setup. I will discuss the experimental setups, photoionization schemes, the achieved 3% momentum resolution and the 10% sensitivity to exotic particle emissions. The photoionization scheme is a two-stepwise procedure, including the Doppler-free two-photon transition from the 5S_1/2 to the 5D_5/2 states by a 778 nm laser, and from the 5D_5/2 state into the continuum by a 1064 nm laser. By analyzing the measured 5S_1/2 to 5D_5/2 two-photon transition spectra, we deduced the related isotope shifts and hyperfine constants in radioactive Rb isotopes. The precision we achieved in the isotope shift measurements allows us to deduce the specific mass shifts between the 5S_1/2 to 5D_5/2 states with 4 - 28 MHz precision./p>