A5007548594- Particle physics theoretical and experimental studies
- Atomic and Molecular Physics
- Quantum Chromodynamics and Particle Interactions
- Particle Accelerators and Free-Electron Lasers
- Solar and Space Plasma Dynamics
- Particle accelerators and beam dynamics
- Nuclear physics research studies
- Astro and Planetary Science
- Planetary Science and Exploration
- Ionosphere and magnetosphere dynamics
- Muon and positron interactions and applications
- High-Energy Particle Collisions Research
- Seismic Imaging and Inversion Techniques
- Elasticity and Material Modeling
- Geotechnical and Geomechanical Engineering
- Scientific Research and Discoveries
- Elasticity and Wave Propagation
- Advanced NMR Techniques and Applications
- Drilling and Well Engineering
- Rock Mechanics and Modeling
- Neutrino Physics Research
- GNSS positioning and interference
- Dark Matter and Cosmic Phenomena
- Quantum and Classical Electrodynamics
- Magnetic confinement fusion research
Duke University
2021-2024
Southern University of Science and Technology
2022-2024
Triangle Universities Nuclear Laboratory
2021-2024
Sinopec (China)
2021
The Galactic edge, at Galactocentric distances of 14,--,22,kpc, provides an ideal laboratory for studying molecular clouds in environment that is different from the solar neighborhood, due to its lower gas density, metallicity, and little or no perturbation spiral arms. Observations CO,(J,=,2--1) spectral lines were carried out toward 72 located edge using IRAM,30,m telescope. With these observations combined with CO,(J,=,1--0) data MWISP project, we investigated variations R_21 across...
In the absence of fracture, strata with horizontal interbedding structure can be approximately equivalent to transversely isotropic media vertical axis symmetry (VTI) in sedimentary basin. Accurate estimation Young's modulus, Poisson's ratio, and weak anisotropy (WA) parameters provide basic information for further prediction shale reservoir rock brittleness <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in situ</i> stress. Based on...
Abstract Linear instability analysis as well a corresponding two‐dimensional hybrid simulation are performed to examine the excitation of proton cyclotron waves observed upstream Mars. The believed be excited by pickup ions produced from ionization Martian hydrogen exosphere. And previous statistical wave observations suggested that mostly related ion beam velocity distributions. While earlier linear distributions has mainly been focused on parallel unstable modes, our reveals maximum growth...
To extract the charge radius of proton, ${r}_{p}$, from electron scattering data, PRad collaboration at Jefferson Lab has developed a rigorous framework for finding best functional forms---the fitters---for robust extraction ${r}_{p}$ wide variety sample functions range and uncertainties data. In this paper we utilize further develop framework. Herein discuss methods searching fitter candidates as well procedure testing robustness deuteron radius, ${r}_{d}$, parametrizations based on elastic...
Abstract The solar wind deceleration upstream of the Martian bow shock is examined using particle and magnetic field measurements obtained by Mars Atmosphere Volatile EvolutioN (MAVEN). lacks a strong intrinsic so its upper atmosphere extends beyond interacts directly with wind. Neutral atoms in can be ionized through several physical processes then start to move flow form pickup ions. In return, expected slow down due momentum transfer present study surveys MAVEN between 2015 2019 evaluate...
Abstract Proton cyclotron waves (PCWs) upstream of Mars are thought to be associated with the instabilities pickup ions. The ions ring distributions have larger maximum growth rates compared beam distributions. However, observations revealed a notably‐reduced occurrence rate PCWs for Linear instability analysis and corresponding two‐dimensional particle‐in‐cell (PIC) simulation performed investigate ion Mars. indicates that distribution is unstable cyclotron, Bernstein, mirror instabilities....
Abstract We report the first statistical survey of oxygen ion cyclotron harmonic waves observed by Van Allen Probes throughout mission. Our study shows that occurred over 2 < L 6 and across all magnetic local time. More than 50% events were just outside plasmapause, typical wave amplitude is between ∼0.1 several nT. The frequency spacing two consecutive harmonics decreases with increasing but stabilizes when > 5. larger gyrofrequency for many events, especially those at , suggesting...
Systematic differences exist between values of the proton's electric form factors in low-${Q}^{2}$ region extracted by different experimental and theoretical groups, though they are all making use basically same electron-proton scattering data. To try to understand source these differences, we make analytically well-behaved rational ($N=1, M=1$) function, a predictive function that can be reasonably used for extrapolations at ${Q}^{2}\ensuremath{\rightarrow}0$. First, test how well this...
A measurement of the double-spin asymmetry from electron-$^{3}$He scattering in threshold region two- and three-body breakup $^{3}$He was performed at Jefferson Lab, for Q$^{2}$ values 0.1 0.2 (GeV/$c$)$^{2}$. The results this serve as a stringent test our understanding few-body systems. When compared with calculations plane wave impulse approximation Faddeev theory, we found that calculations, which use modern nuclear potentials prescriptions meson-exchange currents, demonstrate an overall...
The first measurement of the $\vec{^3He}(\vec{\gamma},p)d$ process was performed at High Intensity $\gamma$-ray Source (HI$\gamma$S) facility Triangle Universities Nuclear Laboratory (TUNL) using a circularly polarized, monoenergetic beam and longitudinally polarized $^3$He target. spin-dependent asymmetry contribution from two-body photodisintegration to Gerasimov-Drell-Hearn integrand are extracted compared with state-of-the-art three-nucleon system calculations incident photon energy 29.0...
In our quest to understand the nature of dark matter and discover its non-gravitational interactions with ordinary matter, we propose an experiment using a \pbo ~calorimeter search for or set new limits on production rate i) hidden sector particles in $3 - 60$ MeV mass range via their $e^+e^-$ decay (or $\gamma\gamma$ limited tracking), ii) hypothetical X17 particle, claimed multiple recent experiments. The these is motivated by models candidates introduced account variety experimental...
Analogous to the well-known proton charge radius puzzle, a similar puzzle exists for deuteron radius, $r_{d}$. There are discrepancies observed in results of $r_{d}$, measured from electron-deuteron ($e-d$) scattering experiments, as well atomic spectroscopy. In order help resolve deuteron, PRad collaboration at Jefferson Lab has proposed an experiment measuring named DRad. This is designed measure unpolarized elastic $e-d$ cross section low-$Q^{2}$ region. To extract with high precision,...
Abstract The proton charge radius and nucleon electromagnetic polarizabilities are fundamental properties probing the structure of nucleons. Proton is directly related to distribution characterize response charge/magnetic constituents inside external fields. A precise understanding these quantities crucial not only for how Quantum Chromodynamics (QCD) works in non-perturbative QCD region but also bound state Electrodynamics (QED) calculations atomic energy levels. We discuss experimental...
&lt;p&gt;We report the first statistical survey of oxygen ion cyclotron harmonic waves observed by Van Allen Probes throughout mission. An example event on 19 February 2014 after a strong magnetic storm and substorm was presented to demonstrate general properties OCH waves. The have multiple spectral peaks around harmonics gyrofrequency. During event, ions&lt;sup&gt;&lt;/sup&gt;of 10s keV had ring-like partial shell velocity distribution which might driven wave...
Systematic differences exist between values of the proton's electric form factors in low-$Q^2$ region extracted by different experimental and theoretical groups, though they are all making use basically same electron-proton scattering data. To try understand source these differences, we make analytically well-behaved rational (N=1, M=1) function, a predictive function that can be reasonably used for extrapolations at $Q^{2} \rightarrow 0$. First, test how well this deceptively simple...