A5075830372- Quantum Chromodynamics and Particle Interactions
- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Nuclear physics research studies
- Dark Matter and Cosmic Phenomena
- Atomic and Molecular Physics
- Nuclear Physics and Applications
- Advanced NMR Techniques and Applications
- Atomic and Subatomic Physics Research
- Quantum, superfluid, helium dynamics
- Black Holes and Theoretical Physics
- Neutrino Physics Research
- Superconducting Materials and Applications
- Cold Atom Physics and Bose-Einstein Condensates
- High-pressure geophysics and materials
- Pulsars and Gravitational Waves Research
- Particle Accelerators and Free-Electron Lasers
- Crystallography and Radiation Phenomena
- Particle accelerators and beam dynamics
- Advanced Chemical Physics Studies
- Particle Detector Development and Performance
- Scientific Research and Discoveries
- Nuclear reactor physics and engineering
- Astrophysics and Cosmic Phenomena
- Quantum chaos and dynamical systems
The University of Texas at Austin
2003-2025
University of Washington
2015-2024
University of Manchester
2007-2024
The Ohio State University
2020
The Graduate Center, CUNY
2018
Baruch College
2018
Massachusetts Institute of Technology
2017
Seattle University
1978-2016
Lawrence Berkeley National Laboratory
2012
Williams (United States)
2012
Cross sections for inelastic scattering of electrons from hydrogen were measured incident energies 7 to 17 GeV at angles 6\ifmmode^\circ\else\textdegree\fi{} 10\ifmmode^\circ\else\textdegree\fi{} covering a range squared four-momentum transfers up 7.4 ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^{2}$. For low center-of-mass the final hadronic system cross section shows prominent resonances momentum transfer and diminishes markedly higher transfer. high excitations only weak...
By incorporating chiral invariance in the MIT bag model, we are led to a theory which pion field is coupled confined quarks only at surface. An equivalent quantized of nucleons and $\ensuremath{\Delta}'\mathrm{s}$ interacting with pions then obtained. The pion-nucleon scattering amplitude this model found give good fit experimental data on (3,3) resonance, radius about 0.72 fm.
A previously derived model in which a baryon is treated as three-quark bag that surrounded by cloud of pions used to compute the static properties nucleon. The only free parameter radius fixed fit pion-nucleon scattering (3,3)-resonance region be about 0.8 fm. With so determined computed values root-mean-square radii and magnetic moments neutron proton, ${g}_{A}$, are all very good agreement with experimental values. In addition, one-third $\ensuremath{\Delta}$-nucleon mass splitting found...
The extremely precise extraction of the proton radius by Pohl et al. from measured energy difference between 2P and 2S states muonic hydrogen disagrees significantly with that extracted electronic or elastic electron-proton scattering. This is puzzle. origins puzzle reasons for believing it to be very significant are explained. Various possible solutions identified, future work needed resolve discussed.
This article reviews our current understanding of how the internal quark structure a nucleon bound in nuclei differs from that free nucleon. We focus on interpretation measurements EMC effect for valence quarks, reduction Deep Inelastic Scattering (DIS) cross-section ratios relative to deuterium, and its possible connection nucleon-nucleon Short-Range Correlations (SRC) nuclei. Our review new analysis (involving amplitudes non-nucleonic configurations nucleus) available experimental...
A model-independent analysis of the infinite-momentum-frame charge density partons in transverse plane is presented for nucleon. We find that neutron-parton negative at center, so square radius positive, contrast with many expectations. Additionally, proton's central d quark larger than u by about 30%. The proton (neutron) has a long range positively (negatively) charged component.
Nuclear Forces: A Review Matter The Shell Model Many-Particle Why Field Theory QCD and a Phase Transition Pions Dynamic Resonances Path Integrals Strong-Coupling Limit Include Fermions Quarks in the Standard Semileptonic Weak Processes other topics.
Differential cross sections for electrons scattered inelastically from hydrogen have been measured at 18\ifmmode^\circ\else\textdegree\fi{}, 26\ifmmode^\circ\else\textdegree\fi{}, and 34\ifmmode^\circ\else\textdegree\fi{}. The range of incident energy was 4.5 to 18 GeV, the four-momentum transfer squared 1.5 21 ${(\frac{\mathrm{GeV}}{c})}^{2}$. With use these data in conjunction with previously 6\ifmmode^\circ\else\textdegree\fi{} 10\ifmmode^\circ\else\textdegree\fi{}, contributions...
Electromagnetic form factors have long been used to probe the underlying charge and magnetization densities of hadrons nuclei. Traditional three-dimensional Fourier transform methods are not rigorously applicable for systems with constituents that move relativistically. The use transverse density is a new, defined way analyze electromagnetic hadrons.This review concerned following issues: what density; how one extracted from elastic scattering data; existing results; relationship other...
Background: There is significant current interest in knowing the value of proton radius and also its proper definition. Purpose: Combine disparate literatures hydrogen spectroscopy diverse modern parton distributions to understand meaning a manner consistent with separate bodies work. Methods: Use perturbation theory, light-front dynamics, elementary techniques find relativistically correct definitions charge density. Results: It found that very same accessed by measurements elastic lepton...
Abstract The workshop “Shedding light on X17” brings together scientists looking for the existence of a possible new particle, often referred to as X17. This hypothetical particle can explain resonant structure observed at $$\sim $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mo>∼</mml:mo> </mml:math> 17 MeV in invariant mass electron-positron pairs, produced after excitation nuclei such $$^8\hbox {Be}$$ <mml:mrow> <mml:msup> <mml:mrow /> <mml:mn>8</mml:mn> </mml:msup>...
A detailed formulation of the Hamiltonian formalism, together with a consistent renormalization procedure, is described for cloudy bag model. The electromagnetic properties nucleon are calculated center-of-mass corrections included. Good agreement experimental results obtained radii ranging from 0.8 to 1.0 fm.
The nucleon is modeled, using light front dynamics, as a relativistic system of three bound constituent quarks surrounded by cloud pions. pionic important for understanding low-momentum transfer physics, especially the neutron charge radius, but are dominant at high values ${Q}^{2}.$ model achieves very good description existing data four electromagnetic elastic form factors.
Recent developments in understanding the influence of nucleus on deep-inelastic structure functions, EMC effect, are reviewed. A new data base which expresses ratios functions terms Bjorken variable x = AQ 2 /(2M q 0 ) is presented. Information about two-nucleon short-range correlations (SRC) from experiments also discussed and remarkable linear relation between SRC effect convolution model that relates underlying source to modification either mean-field nucleons or It shown both approaches...
We develop a technique, denoted as the finite radius approximation (FRA), that uses two-dimensional version of Shannon-Nyquist sampling theorem to determine transverse densities and their uncertainties from experimental quantities. Uncertainties arising on form factors lack measured data at high $Q^2$ are treated. A key feature FRA is factor given value related definite region in coordinate space. An exact relation between use Bessel series derived. The proton Dirac well enough known such...
We update the determination of isovector nucleon electromagnetic self-energy, valid to leading order in QED. A technical oversight literature concerning elastic contribution Cottingham's formula is corrected and modern knowledge structure functions used precisely determine inelastic contribution. find \delta M_{p-n}^\gamma = 1.30(03)(47) MeV. The largest uncertainty arises from a subtraction term required dispersive analysis, which can be related magnetic polarizability. With plausible model...