A5107027172- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Particle Detector Development and Performance
- Nuclear physics research studies
- Particle Accelerators and Free-Electron Lasers
- Atomic and Subatomic Physics Research
- Radiation Detection and Scintillator Technologies
- Superconducting Materials and Applications
- Nuclear Physics and Applications
- Atomic and Molecular Physics
- Cold Fusion and Nuclear Reactions
- Dark Matter and Cosmic Phenomena
- Advanced NMR Techniques and Applications
- Electron and X-Ray Spectroscopy Techniques
- Advanced Data Storage Technologies
- Particle accelerators and beam dynamics
- Quantum, superfluid, helium dynamics
- Photocathodes and Microchannel Plates
- Magnetic confinement fusion research
- Distributed and Parallel Computing Systems
- Neutrino Physics Research
- Physics of Superconductivity and Magnetism
- Medical Imaging Techniques and Applications
- X-ray Spectroscopy and Fluorescence Analysis
University of Cambridge
2025
Catholic University of America
2015-2024
Thomas Jefferson National Accelerator Facility
2015-2024
University of America
2015-2024
William & Mary
2024
Williams (United States)
2024
American University
2024
University of Kentucky
2024
Duquesne University
2022-2023
Shandong University
2023
This White Paper presents the science case of an Electron-Ion Collider (EIC), focused on structure and interactions gluon-dominated matter, with intent to articulate it broader nuclear community. It was commissioned by managements Brookhaven National Laboratory (BNL) Thomas Jefferson Accelerator Facility (JLab) objective presenting a summary scientific opportunities goals EIC as follow-up 2007 NSAC Long Range plan. document is culmination community-wide effort in following series workshops...
This report is based on a ten-week program Gluons and the quark sea at high-energies, which took place Institute for Nuclear Theory (INT) in Seattle Fall 2010. The principal aim of was to develop sharpen science case an Electron-Ion Collider (EIC), facility that will be able collide electrons positrons with polarized protons light heavy nuclei high energies, offering unprecedented possibilities in-depth studies quantum chromodynamics (QCD). organized around following four major themes: (i)...
Among the most fundamental observables of nucleon structure, electromagnetic form factors are a crucial benchmark for modern calculations describing strong interaction dynamics nucleon's quark constituents; indeed, recent proton data have attracted intense theoretical interest. In this Letter, we report new measurements factor ratio using recoil polarization method, at momentum transfers Q2=5.2, 6.7, and 8.5 GeV2. By extending range Q2 which G(E)(p) is accurately determined by more than 50%,...
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.
We have measured parity-violating asymmetries in elastic electron-proton scattering over the range of momentum transfers 0.12 < or =Q2 =1.0 GeV2. These asymmetries, arising from interference electromagnetic and neutral weak interactions, are sensitive to strange-quark contributions currents proton. The measurements were made at Jefferson Laboratory using a toroidal spectrometer detect recoiling protons liquid hydrogen target. results indicate nonzero, Q2 dependent, provide new information...
The $^{1}\mathrm{H}(e,{e}^{\ensuremath{'}}{\ensuremath{\pi}}^{+})n$ cross section was measured at four-momentum transfers of ${Q}^{2}=1.60$ and $2.45\text{ }\text{ }{\mathrm{GeV}}^{2}$ an invariant mass the photon nucleon system $W=2.22\text{ }\mathrm{GeV}$. charged pion form factor (${F}_{\ensuremath{\pi}}$) extracted from data by comparing separated longitudinal electroproduction to a Regge model prediction in which ${F}_{\ensuremath{\pi}}$ is free parameter. results indicate that deviates...
The charged pion form factor, ${F}_{\ensuremath{\pi}}({Q}^{2})$, is an important quantity that can be used to advance our knowledge of hadronic structure. However, the extraction ${F}_{\ensuremath{\pi}}$ from data requires a model ${}^{1}\mathrm{H}(e,{e}^{'}{\ensuremath{\pi}}^{+})n$ reaction and thus inherently dependent. Therefore, detailed description factor electroproduction obtained recently at Jefferson Lab presented, with particular focus given dominant uncertainties in this procedure....
This White Paper presents the science case of an Electron-Ion Collider (EIC), focused on structure and interactions gluon-dominated matter, with intent to articulate it broader nuclear community. It was commissioned by managements Brookhaven National Laboratory (BNL) Thomas Jefferson Accelerator Facility (JLab) objective presenting a summary scientific opportunities goals EIC as follow-up 2007 NSAC Long Range plan. document is culmination community-wide effort in following series workshops...
New Jefferson Lab data are presented on the nuclear dependence of inclusive cross section from $^{2}\mathrm{H}$, $^{3}\mathrm{He}$, $^{4}\mathrm{He}$, $^{9}\mathrm{Be}$ and $^{12}\mathrm{C}$ for $0.3<x<0.9$, ${Q}^{2}\ensuremath{\approx}3--6\text{ }\text{ }{\mathrm{GeV}}^{2}$. These represent first measurement EMC effect $^{3}\mathrm{He}$ at large $x$ a significant improvement $^{4}\mathrm{He}$. The do not support previous $A$-dependent or density-dependent fits to suggest that quark...
We report on measurements of the neutron spin asymmetries An1,2 and polarized structure functions gn1,2 at three kinematics in deep inelastic region, with x=0.33, 0.47, 0.60 Q2=2.7, 3.5, 4.8(GeV∕c)2, respectively. These were performed using a 5.7GeV longitudinally electron beam 3He target. The results for An1 gn1 x=0.33 are consistent previous world data and, two higher-x points, have improved precision by about an order magnitude. new show zero crossing around x=0.47 value x=0.60 is...
We present new measurements of electron scattering from high-momentum nucleons in nuclei. These data allow an improved determination the strength two-nucleon correlations for several nuclei, including light nuclei where clustering effects can, first time, be examined. The also include kinematic region three-nucleon are expected to dominate.
We have measured parity-violating asymmetries in elastic electron-proton and quasielastic electron-deuteron scattering at ${Q}^{2}=0.22$ $0.63\text{ }\text{ }{\mathrm{GeV}}^{2}$. They are sensitive to strange quark contributions currents the nucleon axial-vector current. The results indicate of $\ensuremath{\lesssim}10%$ charge magnetic form factors these four-momentum transfers. also present first measurement anapole moment effects current
Almost 50 years after the discovery of gluons & quarks, we are only just beginning to understand how QCD builds basic bricks for nuclei: neutrons, protons, and pions that bind them. is characterised by two emergent phenomena: confinement dynamical chiral symmetry breaking (DCSB). They expressed with great force in character pion. In turn, pion properties suggest DCSB closely connected. As both a Nambu-Goldstone boson quark-antiquark bound-state, unique Nature. Developing an understanding its...
How the bulk of Universe's visible mass emerges and how it is manifest in existence properties hadrons are profound questions that probe into heart strongly interacting matter. Paradoxically, lightest pseudoscalar mesons appear to be key further understanding emergent structure mechanisms. These mesons, namely pion kaon, Nambu-Goldstone boson modes QCD. Unravelling their partonic interplay between Higgs-boson mechanisms a common goal three interdependent approaches -- continuum QCD...
We have measured the neutron spin asymmetry A(n)(1) with high precision at three kinematics in deep inelastic region x=0.33, 0.47, and 0.60, Q(2)=2.7, 3.5, 4.8 (GeV/c)(2), respectively. Our results unambiguously show, for first time, that crosses zero around x=0.47 becomes significantly positive x=0.60. Combined world proton data, polarized quark distributions were extracted. results, general, agree relativistic constituent models perturbative quantum chromodynamics (PQCD) analyses based on...
Cross sections for the reaction ${}^{1}\mathrm{H}(e,{e}^{'}{\ensuremath{\pi}}^{+})n$ were measured in Hall C at Thomas Jefferson National Accelerator Facility (JLab) using high-intensity Continuous Electron Beam (CEBAF) to determine charged pion form factor. Data taken central four-momentum transfers ranging from ${Q}^{2}=0.60$ 2.45 ${\mathrm{GeV}}^{2}$ an invariant mass of virtual photon-nucleon system $W=1.95$ and 2.22 GeV. The cross separated into four structure functions...
Intensive theoretical and experimental efforts over the past decade have aimed at explaining discrepancy between data for proton electric to magnetic form factor ratio, G(E)/G(M), obtained separately from cross section polarization transfer measurements. One possible explanation this difference is a two-photon-exchange contribution. In an effort search effects beyond one-photon-exchange or Born approximation, we report measurements of observables in elastic H(e[over →],e(')p[over →])...
The GEp-III and GEp-2$\gamma$ experiments were carried out in Jefferson Lab's (JLab's) Hall C from 2007-2008, to extend the knowledge of $G_E^p/G_M^p$ highest practically achievable $Q^2$ search for effects beyond Born approximation polarization transfer observables elastic $\vec{e}p$ scattering. This article reports an expanded description common experimental apparatus data analysis procedure, results a final reanalysis both experiments, including previously unpublished full-acceptance...
An experiment with a newly developed high-resolution kaon spectrometer (HKS) and scattered electron novel configuration was performed in Hall C at Jefferson Lab (JLab). The ground state of neutron-rich hypernucleus, He 7 Lambda, observed for the first time (e,e'K+) reaction an energy resolution ~0.6 MeV. This is best reported to date hypernuclear spectroscopy. he Lambda binding supplies last missing information A=7, T=1 iso-triplet, providing new input charge symmetry breaking (CSB) effect...
Spectroscopy of a $^{10}_{\Lambda}$Be hypernucleus was carried out at JLab Hall C using the $(e,e^{\prime}K^{+})$ reaction. A new magnetic spectrometer system (SPL+HES+HKS), specifically designed for high resolution hypernuclear spectroscopy, used to obtain an energy spectrum with 0.78 MeV (FWHM). The well-calibrated present experiment $p(e,e^{\prime}K^{+})\Lambda,\Sigma^{0}$ reactions allowed us determine levels, and binding ground state peak (mixture 1$^{-}$ 2$^{-}$ states) obtained be...
The topical workshop Strong QCD from Hadron Structure Experiments took place at Jefferson Lab November 6–9, 2019. Impressive progress in relating hadron structure observables to the strong mechanisms has been achieved ab initio description of a diverse array methods order expose emergent phenomena via quasi-particle formation. wealth experimental data and advances theory make it possible gain insight into interaction dynamics regime large quark–gluon coupling (the regime), which will address...
The 1H(e,e′π+)n cross section was measured for arange of four-momentum transfer up to Q2=3.91GeV2 at values the invariant mass W above resonance region. Q2 dependence longitudinal component found be consistent with Q2-scaling prediction hard exclusive processes. This suggests that QCD factorization theorem is applicable rather low Q2. transverse term falls off slower than naive Q−8 expectation and remains appreciable even Q2=3.91GeV2.Received 12 July...