A5033041764- Nuclear physics research studies
- Nuclear Physics and Applications
- Atomic and Molecular Physics
- Nuclear reactor physics and engineering
- X-ray Spectroscopy and Fluorescence Analysis
- Astronomical and nuclear sciences
- Quantum Chromodynamics and Particle Interactions
- Particle physics theoretical and experimental studies
- Gamma-ray bursts and supernovae
- Medical Imaging Techniques and Applications
- Advanced Chemical Physics Studies
- Particle accelerators and beam dynamics
- Astro and Planetary Science
- Atomic and Subatomic Physics Research
- Radiation Detection and Scintillator Technologies
- Advanced NMR Techniques and Applications
- Ionosphere and magnetosphere dynamics
- Neutrino Physics Research
- Quantum, superfluid, helium dynamics
- Inorganic Fluorides and Related Compounds
- Graphite, nuclear technology, radiation studies
- Particle Detector Development and Performance
- Nuclear and radioactivity studies
- Earthquake Detection and Analysis
- Radioactive contamination and transfer
Oak Ridge National Laboratory
2015-2024
Briar Cliff University
2024
Purdue University West Lafayette
2024
University of Cincinnati Medical Center
2023
Thomas Jefferson National Accelerator Facility
2022
University of North Carolina Wilmington
1995-2022
Mount Sinai Hospital
2017-2022
National Technical Information Service
2020
Lawrence Livermore National Laboratory
2017-2020
Brookhaven National Laboratory
2020
view Abstract Citations (421) References (184) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Experimental, Computational, and Observational Analysis of Primordial Nucleosynthesis Smith, Michael S. ; Kawano, Lawrence H. Malaney, Robert A. We present a comprehensive evaluation the current status standard theory primordial nucleosynthesis, determining 12 nuclear reactions most important for production light elements conducting detailed study their rates...
Abstract The European Space Agency's three Swarm satellites were launched on 22 November 2013 into nearly polar, circular orbits, eventually reaching altitudes of 460 km (Swarm A and C) 510 B). Swarm's multiyear mission is to make precision, multipoint measurements low‐frequency magnetic electric fields in Earth's ionosphere for the purpose characterizing generated both inside external Earth, along with other plasma parameters associated current systems magnetosphere. Electric perpendicular...
Advances in machine learning methods provide tools that have broad applicability scientific research. These techniques are being applied across the diversity of nuclear physics research topics, leading to advances will facilitate discoveries and societal applications. This Review gives a snapshot which has been transformed by techniques.
The rate of the (17)F(p,gamma)(18)Ne reaction is important in various astrophysical events. A previous (17)F(p,p)(17)F measurement identified a 3;{+} state providing strongest resonance contribution, but strength was unknown. We have directly measured using mixed beam (17)F and (17)O at ORNL. for (18)Ne found to be omegagamma = 33 +/- 14(stat) +/-1 7(syst) meV, corresponding gamma width Gamma_{gamma} 56 24(stat) 30(syst) meV. An upper limit on direct capture S(E) <or= 65 keV b determined an...
The best examples of halo nuclei, exotic systems with a diffuse nuclear cloud surrounding tightly bound core, are found in the light, neutron-rich region, where neutrons experience only weak binding and weak, or no, potential barrier. Modern direct-reaction measurement techniques provide powerful probes structure nuclei. Despite more than four decades these studies on benchmark one-neutron nucleus 11Be, spectroscopic factors for two states remain poorly constrained. In present work,...
Knowledge of the astrophysical rate ${}^{18}\mathrm{F}(p,\ensuremath{\alpha}{)}^{15}\mathrm{O}\mathrm{}$ reaction is important for understanding \ensuremath{\gamma}-ray emission expected from novae and heavy-element production in x-ray bursts. The this dominated at temperatures above $\ensuremath{\sim}0.4$ GK by a resonance near 7.08 MeV excitation energy ${}^{19}\mathrm{Ne}.$ ${}^{18}\mathrm{F}(p,\ensuremath{\alpha}{)}^{15}\mathrm{O}$ has been uncertain part because disagreements among...
The ${}^{17}\mathrm{F}(p,\ensuremath{\gamma}{)}^{18}\mathrm{Ne}$ reaction is important in stellar explosions, but its rate has been uncertain because of an expected ${3}^{+}$ state ${}^{18}\mathrm{Ne}$ that never conclusively observed. This would provide a strong $\ensuremath{\ell}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0$ resonance and, depending on excitation energy, could dominate the rate. We have observed this missing by measuring...
The (d,p) neutron transfer and (d,d) elastic scattering reactions were measured in inverse kinematics using a radioactive ion beam of 132Sn at 630 MeV. data taken region where Rutherford dominated the reaction, nuclear effects account for less than 8% cross section. magnitude was found to be independent optical potential used, allowing normalized reliable manner. neutron-transfer reaction populated previously unmeasured state 1363 keV, which is most likely single-particle 3p1/2 expected...
Recent calculations suggest that the rate of neutron capture by $^{130}\mathrm{Sn}$ has a significant impact on late-time nucleosynthesis in $r$ process. Direct into low-lying bound states is expected to be near $N=82$ closed shell, so $r$-process reaction rates may strongly impacted properties single particle this region. In order investigate these properties, ($d$,$p$) been studied inverse kinematics using 630 MeV beam ($4.8\text{ }\text{ }\mathrm{MeV}/\mathrm{u}$) and...
Single-neutron states in $^{133}\mathrm{Sn}$ and $^{209}\mathrm{Pb}$, which are analogous to single-electron outside of closed atomic shells alkali metals, were populated by the ($^{9}\mathrm{Be}$, $^{8}\mathrm{Be}$) one-neutron transfer reaction inverse kinematics using particle-$\ensuremath{\gamma}$ coincidence spectroscopy. In addition, ${s}_{1/2}$ single-neutron hole-state candidate $^{131}\mathrm{Sn}$ was $^{10}\mathrm{Be}$). Doubly closed-shell $^{132}\mathrm{Sn}$ (radioactive)...
Production of the radioisotope 18F in novae is severely constrained by rate 18F(p,alpha)15O reaction. A resonance at E(c.m.)=330 keV may strongly enhance reaction rate, but its strength has been very uncertain. We have determined this important measuring cross section on and off using a radioactive beam ORNL Holifield Radioactive Ion Beam Facility. find that 1.48+/-0.46 eV, it dominates over significant range temperatures characteristic ONeMg novae.
We have studied the properties of low-lying ${}^{18}\mathrm{F}+p$ resonances as excited states in ${}^{19}\mathrm{Ne}.$ Three new levels been found range $0<~{E}_{\mathrm{c}.\mathrm{m}.}<~1 \mathrm{MeV}$ just above threshold, and partial decay widths isospin-mirror connections are suggested to known ${}^{19}\mathrm{F}$ for each nine this energy range. The these used calculate reaction rate ${N}_{A}〈\ensuremath{\sigma}v〉$ ${}^{18}\mathrm{F}(p,\ensuremath{\gamma}{)}^{19}\mathrm{Ne}$...
We used the $^{16}\mathrm{O}$${(}^{3}$He,n${)}^{18}$Ne, $^{12}\mathrm{C}$${(}^{12}$C${,}^{6}$He${)}^{18}$Ne, and $^{20}\mathrm{Ne}$(p,t${)}^{18}$Ne reactions to study $^{18}\mathrm{Ne}$ states up an excitation energy of 10 MeV, with emphasis on levels corresponding $^{14}\mathrm{O}$(\ensuremath{\alpha},p${)}^{17}$F $^{17}\mathrm{F}$(p,\ensuremath{\gamma}${)}^{18}$Ne resonances that could strongly affect these reaction rates in hot stellar environments. Excitation energies, widths, absolute...
Big Bang nucleosynthesis calculations, constrained by the Wilkinson Microwave Anisotropy Probe results, produce ${}^{7}$Li abundances almost a factor of four larger than those extrapolated from observations. Since primordial is believed to be mostly produced beta decay ${}^{7}$Be, one proposed solution this discrepancy resonant enhancement ${}^{7}$Be($d,p$)2$\ensuremath{\alpha}$ reaction rate through 5/2${}^{+}$ 16.7-MeV state in ${}^{9}$B. The ${}^{2}$H(${}^{7}$Be,$d$)${}^{7}$Be was used...
The extraction of detailed nuclear structure information from transfer reactions requires reliable, well-normalized data as well optical potentials and a theoretical framework demonstrated to work in the relevant mass beam energy ranges. It is rare that ingredients can be tested for exotic nuclei owing paucity data. halo nucleus Be-11 has been examined through 10Be(d,p) reaction inverse kinematics at equivalent deuteron energies 12,15,18, 21.4 MeV. Elastic scattering Be-10 on protons was...
Recent reaction measurements have been interpreted as evidence of a halo structure in the exotic neutron-rich isotopes 29,31Ne. While theoretical studies 31Ne generally agree on its nature, they differ significantly their predictions properties and underlying cause (e.g., that has an inverted ordering p–f orbitals). We made systematic analysis possible Neon signatures – first using fully microscopic, relativistic mean field approach properly treats positive energy orbitals (such valence...
▪ Abstract Radioactive nuclei play an important role in a diverse range of astrophysical phenomena including the early universe, sun, red giant stars, nova explosions, X-ray bursts, supernova and supermassive stars. Measurements reactions with beams short-lived radioactive can, for first time, probe nuclear occurring these cosmic phenomena. This article describes motivation experiments beams, techniques to produce perform astrophysically relevant measurements, results from recent...
The cross section for the astrophysically important $^{17}O(p,\ensuremath{\alpha})^{14}N$ reaction was measured at proton energies of 75 and 65 keV. Thick, high-purity ${\mathrm{Ta}}_{2}{O}_{5}$ targets (77% enriched $^{17}O$) large-area detectors were used with beam currents 0.45 mA. Backgrounds using natural isotopic composition. expected resonance ${E}_{p}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}70$ keV observed in data taken keV, its width found to be...
Knowledge of the ${}^{17}\mathrm{F}(p,\ensuremath{\gamma}{)}^{18}\mathrm{Ne}$ reaction rate is important for understanding stellar explosions, but it was uncertain because properties an expected previously unobserved ${3}^{+}$ state in ${}^{18}\mathrm{Ne}$ were not known. This would provide a strong s-wave resonance ${}^{17}\mathrm{F}+p$ system and, depending on its excitation energy, could dominate at temperatures above 0.2 GK. We have observed this missing by measuring...