A5047941039- Nuclear physics research studies
- Nuclear Physics and Applications
- Astronomical and nuclear sciences
- Nuclear reactor physics and engineering
- Quantum Chromodynamics and Particle Interactions
- Radiation Detection and Scintillator Technologies
- Particle physics theoretical and experimental studies
- Particle accelerators and beam dynamics
- Atomic and Molecular Physics
- Gamma-ray bursts and supernovae
- Superconducting Materials and Applications
- Particle Detector Development and Performance
- Neutrino Physics Research
- Dark Matter and Cosmic Phenomena
- Electron and X-Ray Spectroscopy Techniques
- X-ray Spectroscopy and Fluorescence Analysis
- High-pressure geophysics and materials
- Radiation Therapy and Dosimetry
- Astro and Planetary Science
- Atomic and Subatomic Physics Research
- Advanced NMR Techniques and Applications
- Nanopore and Nanochannel Transport Studies
- Nuclear Materials and Properties
- Distributed and Parallel Computing Systems
- Membrane Separation Technologies
Los Alamos National Laboratory
2010-2025
University of Tennessee at Knoxville
2016-2024
The University of Sydney
2022
Joint Institute for Nuclear Astrophysics
2009-2021
University of Notre Dame
2012-2021
Michigan State University
2008-2017
GSI Helmholtz Centre for Heavy Ion Research
2016-2017
University of Rochester
2013-2017
National Superconducting Cyclotron Laboratory
2008-2016
University of California, Santa Cruz
2010
We present results from the JINA REACLIB project, an ongoing effort to maintain a current and accurate library of thermonuclear reaction rates for astrophysical applications. Ongoing updates are transparently documented version tracked, any set is publicly available can be downloaded via Web interface at http://groups.nscl.msu.edu/jina/reaclib/db/. discuss here our V1.0, snapshot recommended stable explosive hydrogen helium burning. show that updated lead modest but significant changes in...
The ${}^{12}$C(\ensuremath{\alpha},\ensuremath{\gamma})${}^{16}$O reaction is essential for the production of carbon and oxygen in Universe, also composition stellar cores after helium burning, a key determinant supernova explosions. This review summarizes current experimental understanding, theoretical underpinning, interpretation data this critical reaction. It shown that desired level uncertainty, \ensuremath{\approx}10%, may be sight, but several inconsistencies need to overcome. Ways...
X-ray bursts are thermonuclear flashes on the surface of accreting neutron stars and reliable burst models needed to interpret observations in terms properties star binary system. We investigate dependence uncertainties (p,$\gamma$), ($\alpha$,$\gamma$), ($\alpha$,p) nuclear reaction rates using fully self-consistent that account for feedbacks between changes energy generation astrophysical conditions. A two-step approach first identified sensitive a single-zone model with ignition...
The $\beta$-delayed neutron emission probabilities of rich Hg and Tl nuclei have been measured together with $\beta$-decay half-lives for 20 isotopes Au, Hg, Tl, Pb Bi in the mass region N$\gtrsim$126. These are heaviest species where has observed so far. measurements provide key information to evaluate performance nuclear microscopic phenomenological models reproducing high-energy part strength distribution. In doing so, it provides important constraints global theoretical currently used...
The neutron-capture reaction plays a critical role in the synthesis of elements stars and is important for societal applications including nuclear power generation stockpile-stewardship science. However, it difficult-if not impossible-to directly measure neutron capture cross sections exotic, short-lived nuclei that participate these processes. In this Letter we demonstrate new technique which can be used to indirectly determine exotic systems. This makes use (d,p) transfer reaction, has...
Background: The $^{3}\mathrm{He}(\ensuremath{\alpha},\ensuremath{\gamma})^{7}\mathrm{Be}$ reaction is of critical importance in determining the flux solar neutrinos through $pp$-II and $pp$-III chains. For this reason others, description cross section its extrapolation towards low-energy has always been a matter intense debate. While large systematic differences have present past, several recent measurements are all excellent statistical agreement.Purpose: convergence individual experimental...
Dielectric materials are foundational to our modern-day communications, defense, and commerce needs. Although dielectric breakdown is a primary cause of failure these systems, we do not fully understand this process. We analyzed the channel propagation dynamics two distinct types electrical trees. One type trees has been formally classified. observed speed tree exceed 10 million meters per second. These results identify substantial gaps in understanding breakdown, filling paramount design...
Beta-delayed proton emission from nuclides in the neighborhood of 100Sn was studied at National Superconducting Cyclotron Laboratory. The nuclei were produced by fragmentation a 120 MeV/nucleon 112Sn primary beam on Be target. Beam purification provided A1900 Fragment Separator and Radio Frequency Separator. fragments interest identified their decay with NSCL Beta Counting System (BCS) conjunction Segmented Germanium Array (SeGA). 96Cd, 98Ing, 98Inm 99In as beta-delayed emitters, branching...
We present results from recent time-of-flight nuclear mass measurements at the National Superconducting Cyclotron Laboratory Michigan State University. report first of ^{48}Ar and ^{49}Ar find atomic excesses -22.28(31) MeV -17.8(1.1) MeV, respectively. These masses provide strong evidence for closed shell nature neutron number N=28 in argon, which is therefore lowest even-Z element exhibiting shell. The resulting trend binding-energy differences, probes strength shell, compares favorably...
We present mass excesses (ME) of neutron-rich isotopes Ar through Fe, obtained via time flight $B\ensuremath{\rho}$ spectrometry at the National Superconducting Cyclotron Laboratory. Our new results have significantly reduced systematic uncertainties relative to a prior analysis, enabling first determination ME for $^{58,59}\mathrm{Ti},^{62}\mathrm{V},^{65}\mathrm{Cr},^{67,68}\mathrm{Mn}$, and $^{69,70}\mathrm{Fe}$. show $N=34$ subshell weaken Sc vanish Ti, along with absence an $N=40$ Mn....
The slow β-decay of the 68Se waiting point in astrophysical rp-process can principle be bypassed by a sequential two proton capture. rate this reaction sequence depends exponentially on 69Br separation energy. We studied β-delayed emission 69Kr and extracted energy −641(42) keV. In addition, we determined half-life T1/2=28(1) ms an excitation 3153(55) keV isobaric analog state 69Br. X-ray burst model calculations show that regardless values other uncertain masses region, new Sp(Br69) allows...
We present the mass excesses of $^{52--57}\mathrm{Sc}$, obtained from recent time-of-flight nuclear measurements at National Superconducting Cyclotron Laboratory Michigan State University. The masses $^{56}\mathrm{Sc}$ and $^{57}\mathrm{Sc}$ were determined for first time with atomic $\ensuremath{-}24.85(59){(}_{\ensuremath{-}54}^{+0})\text{ }\text{ }\mathrm{MeV}$ $\ensuremath{-}21.0(1.3)\text{ }\mathrm{MeV}$, respectively, where asymmetric uncertainty was included due to possible...
Neutrons produced by the carbon fusion reaction $^{12}\mathrm{C}(^{12}\mathrm{C},n)^{23}\mathrm{Mg}$ play an important role in stellar nucleosynthesis. However, past studies have shown large discrepancies between experimental data and theory, leading to uncertain cross section extrapolation at astrophysical energies. We present first direct measurement that extends deep into energy range along with a new improved technique based on from mirror...
We present the mass excesses of 59-64Cr, obtained from recent time-of-flight nuclear measurements at National Superconducting Cyclotron Laboratory Michigan State University. The 64Cr is determined for first time, with an atomic excess -33.48(44) MeV. find a significantly different two-neutron separation energy S2n trend neutron-rich isotopes chromium, removing previously observed enhancement in binding N=38. Additionally, we extend chromium to N=40, revealing behavior consistent identified...
Precise antineutrino measurements are very sensitive to proper background characterization. We present an improved measurement of the ^{13}C(α,n)^{16}O reaction cross section which constitutes significant for large ν[over ¯] detectors. greatly improve precision and accuracy by utilizing a setup that is neutron energies while making excited state transitions via secondary γ-ray detection. Our results shows 54% reduction in contributions from ^{16}O(3^{-},6.13 MeV) used KamLAND analysis.
The experiment for space radiation analysis is an upcoming project Los Alamos National Laboratory. This 12U CubeSat will be placed in a geosynchronous transfer orbit to make measurements of the charged particle populations belts. Currently, there are no data from CubeSats operating belts, and although GTOsat soon this active development. energetic sensor on board telescope which test mature new technologies use missions. energy range interest 100 keV 1000 MeV protons, 20 electrons.
The cross section of the C13(α,n)O16 reaction is needed for nuclear astrophysics and applications to a precision 10% or better, yet inconsistencies among 50 years experimental studies currently lead an uncertainty ≈15%. Using state-of-the-art neutron detection array, we have performed high resolution differential study covering broad energy range. These measurements result in dramatic improvement extrapolation stellar energies potentially reducing ≈5% resolving long standing discrepancies...
Background: There have been measurements on roughly 230 nuclei that are $\ensuremath{\beta}$-delayed neutron emitters. They range from $^{8}\mathrm{He}$ up to $^{150}\mathrm{La}$. Apart $^{210}\mathrm{Tl}$, with a branching ratio of only 0.007%, no other emitter has measured beyond $A=150$. Therefore, new data needed, particularly in the region heavy around $N=126$, order guide theoretical models and help understand formation third $r$-process peak at $A\ensuremath{\sim}195$.Purpose: To...