A5073777772- Nuclear physics research studies
- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Atomic and Molecular Physics
- Nuclear reactor physics and engineering
- Particle physics theoretical and experimental studies
- Gamma-ray bursts and supernovae
- Nuclear Physics and Applications
- Theoretical and Computational Physics
- Advanced Chemical Physics Studies
- High-pressure geophysics and materials
- Hydraulic and Pneumatic Systems
- X-ray Spectroscopy and Fluorescence Analysis
- Astronomical and nuclear sciences
- Experimental Learning in Engineering
- Pulsars and Gravitational Waves Research
- Statistical Mechanics and Entropy
- Ion-surface interactions and analysis
- Quantum chaos and dynamical systems
- Scientific Research and Discoveries
- Neutrino Physics Research
- Cold Atom Physics and Bose-Einstein Condensates
- Stochastic processes and statistical mechanics
- Nuclear Materials and Properties
- Open Education and E-Learning
Michigan State University
2012-2024
ETH Zurich
2022-2024
Argo-Hytos (Czechia)
2020
National Superconducting Cyclotron Laboratory
2000-2012
Astronomy and Space
1995-2012
TRIUMF
1996
University of Michigan–Dearborn
1995
Iowa State University
1992-1995
University of Washington
1995
Rice University
1995
In nuclear collisions induced by stable or radioactive neutron-rich nuclei a transient state of matter with an appreciable isospin asymmetry as well thermal and compressional excitation can be created. This offers the possibility to study properties in region between symmetric pure neutron matter. this review, we discuss recent theoretical studies equation isospin-asymmetric its relations stars nuclei. Chemical mechanical instabilities liquid-gas phase transition asymmetric are investigated....
Following a major shortage of 99Mo in the 2009–2010 period, concern grew that aging reactor production facilities needed to be replaced. Most producers were using highly enriched 235U (HEU) as target material. The Organisation for Economic Co-...Read More
The disappearance of collective flow in nucleus-nucleus collisions occurs at an incident energy (${\mathit{E}}_{\mathrm{bal}}$) where the attractive scattering dominant low energies balances repulsive high energies. We have performed first systematic study entrance-channel mass dependence and hence ${\mathit{E}}_{\mathrm{bal}}$. new data presented for C+C, Ne+Al, Ar+Sc, Kr+Nb systems show that ${\mathit{E}}_{\mathrm{bal}}$ scales as ${\mathit{A}}^{\mathrm{\ensuremath{-}}1/3}$ A is combined...
The cross section for emitting high energy gamma rays in heavy-ion collisions is calculated a model based on the Boltzmann-Uehling-Uhlenbeck equation. elementary production assumed to be neutron-proton bremsstrahlung. Comparison made with experimental data at bombarding energies from 20 84 MeV/nucleon. calculations are found roughly reproduce spectrum, dependence, and angular distribution. From numerical analysis we conclude that of high-energy \ensuremath{\gamma} limited very early stage collision.
We propose a new theory to treat fluctuation phenomena in heavy-ion reactions. In practical terms, the method is an extension of theories one-body density based on mean-field plus collisional dynamics. exploratory study $^{20}$Ne${+\mathrm{}}^{20}$Ne reaction, we find considerable fragmentation with rapidly falling mass spectrum.
We consider the dependence of collective flow on nuclear surface thickness in a Boltzmann-Uehling-Uhlenbeck transport model heavy ion collisions. Well-defined surfaces are introduced by giving test particles Gaussian density profile constant width. Zeros excitation function as much influenced equation state, and this effect is understood terms simple potential scattering model. Realistic calculations must also take into account medium effects for nucleon-nucleon cross section, impact...
We study the decay of classical systems with regular and chaotic dynamics by investigating escape a particle from container small hole. For case ergodic motion, we find an exponential law, whereas nonchaotic system decays according to power law.
Ionization and multifragmentation have been observed in ${\mathrm{C}}_{60}$ molecules bombarded by ${\mathrm{Xe}}^{35+}$ ${\mathrm{Xe}}^{18+}$ ions with energies the range 420-625 MeV. The c.m. exceeded those used previous studies several orders of magnitude. We present mass distribution positively charged fragments together a theoretical model indicating that total interaction cross section contains roughly equal contributions from (a) excitation giant plasmon resonance, (b)...
Nuclear transport theory predicts the formation of unstable bubbles and rings in central collision between equal-mass heavy ions. This phenomenon occurs around a beam energy E/A\ensuremath{\approxeq}50 MeV/nucleon is due to compression nuclei early stage collision. As observable consequences, we predict higher number intermediate-mass fragments than expected from multifragmentation homogeneously filled sphere, different pattern fragment Coulomb accelerations.
We use a percolation model of nuclear fragmentation to study the possibility observing phase transition matter in collisions high-energy (> 10 GeV) protons with heavy targets. It is shown that able reproduce experimental results for inclusive mass yields, while only using very simple physical assumptions. By employing event by analysis moments distributions it how extract possible signals and information on its specific nature. Special attention focused influence size fragmenting system...
We report the first observation of disappearance flow in heavy-ion collisions. This is accomplished by measuring excitation function average in-plane transverse momentum for symmetric system $^{139}\mathrm{La}$, using beam energies 130, 70, and 50 MeV/nucleon. The indicative a change from dominantly repulsive to attractive scattering. also present results calculations performed with Boltzmann-Uehling-Uhlenbeck equation which support concept vanishing this energy region between 30
A set of coupled transport equations for the phase-space distribution functions nucleons, deltas, and pions is solved with test particle method to study pion production in relativistic heavy ion collisions. The experimentally observed concave shape spectra well reproduced. mechanism that causes found be due different contributions delta resonance produced during early late stages collision energy dependence absorption cross sections. on beam energy, target projectile mass, impact parameter...
We perform an analysis of exclusive heavy-ion reactions around 100 MeV/nucleon in terms multipole moments the momentum distribution nucleons. Numerical calculations based on Boltzmann-Uehling-Uhlenbeck theory are presented and compared to approximate scaling function. find that nuclei completely stop each other even at MeV/nucleon, if ${A}_{P}+{A}_{T}>200$ symmetrical central collisions. propose mass dependence quadrupole tensor can be used determine nuclear compressibility.
The relationship between observed intermediate mass fragment and total charged particle multiplicities has been measured for Kr84 + Au197 collisions at energies E/A=35 400 MeV. Fragment are greatest central or near-central collisions. For these collisions, production increases up to E/A≊100 MeV, then decreases higher energies.Received 14 January 1994DOI:https://doi.org/10.1103/PhysRevC.49.R2271©1994 American Physical Society
Light charged fragments from the reaction $^{40}\mathrm{Ar}$${+}^{51}$V at 35--85 MeV/nucleon in 10 steps have been measured with a 4\ensuremath{\pi} detector. The observed transverse collective momentum central collisions decreases monotonically 45 to 85 MeV/nucleon. data are interpreted assuming that attractive mean-field deflects negative scattering angles. As beam energy is raised, opposed by buildup of compressed nuclear matter. A lower limit 76 placed on where deflection balanced...
An approximate relation is derived which allows the calculation of two-proton correlation function for any reaction model capable predicting classical single-particle phase-space distribution or Wigner in exit channel. The sensitivity calculated functions to source radii and lifetimes illustrated with simple parametrizations. More realistic calculations are presented two different regimes emission time scales: slow particle evaporation from equilibrated compound nuclei, as predicted...
We present Z distributions for fragments with 1\ensuremath{\le}Z\ensuremath{\le}12 from central collisions of $^{40}$ Ar${+}^{45}$Sc at incident energies ranging 35 to 115 MeV/nucleon. find that the can be described by a power law or an exponential and steepen increasing energy. Over range studied, average number intermediate mass decreases while particles increases. When combined previous results charge distributions, minimum is observed in extracted power-law parameter.
We discuss the development and functionality of LON-CAPA system with a particular focus on its homework examination functionality. also describe more general approach to course management infrastructure for content sharing reuse. then measures student learning effectiveness different types.
As a result of the pandemic, many physics courses moved online. Alongside, popularity Internet-based problem-solving sites and forums rose. With emergence large language models, another shift occurred. One year into public availability these how has online help-seeking behavior among introductory students changed, what is effect different patterns resource usage? In mixed-method approach, we investigate student choices their impact on assessment components an course for scientists engineers....