A5012144703- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Nuclear physics research studies
- Superconducting Materials and Applications
- Nuclear Physics and Applications
- Particle Accelerators and Free-Electron Lasers
- Atomic and Subatomic Physics Research
- Radiation Therapy and Dosimetry
- Advanced NMR Techniques and Applications
- Particle Detector Development and Performance
- Radiation Detection and Scintillator Technologies
- Advanced Radiotherapy Techniques
- Neutrino Physics Research
- Quantum, superfluid, helium dynamics
- Atomic and Molecular Physics
- Dark Matter and Cosmic Phenomena
- Particle accelerators and beam dynamics
- Medical Imaging Techniques and Applications
- Advanced Chemical Physics Studies
- X-ray Spectroscopy and Fluorescence Analysis
- Muon and positron interactions and applications
- Radiation Effects and Dosimetry
- Radiopharmaceutical Chemistry and Applications
- Digital Radiography and Breast Imaging
Thomas Jefferson National Accelerator Facility
2015-2024
William & Mary
1997-2024
Williams (United States)
2005-2024
Virginia Tech
2022-2023
Al-Zaytoonah University of Jordan
2023
Shandong University
2023
Hampton University
2012-2022
Massachusetts Institute of Technology
2019
North Carolina Agricultural and Technical State University
2018
University of Regina
2017
We present the new nCTEQ15 set of nuclear parton distribution functions with uncertainties. This fit extends CTEQ proton PDFs to include dependence using data on nuclei all way up 208^Pb. The uncertainties are determined Hessian method an optimal rescaling eigenvectors accurately represent for chosen tolerance criteria. In addition Deep Inelastic Scattering (DIS) and Drell-Yan (DY) processes, we also inclusive pion production from RHIC help constrain gluon PDF. Furthermore, investigate...
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%,...
The MINERvA experiment is designed to perform precision studies of neutrino-nucleus scattering using $\nu_\mu$ and ${\bar\nu}_\mu$ neutrinos incident at 1-20 GeV in the NuMI beam Fermilab. This article presents a detailed description \minerva detector describes {\em ex situ} techniques employed characterize monitor its performance. comprised finely-segmented scintillator-based inner tracking region surrounded by electromagnetic hadronic sampling calorimetry. upstream portion includes planes...
The proton elastic form factors ${\mathit{G}}_{\mathit{E}\mathit{p}}$(${\mathit{Q}}^{2}$) and ${\mathit{G}}_{\mathit{M}\mathit{p}}$(${\mathit{Q}}^{2}$) have been extracted for ${\mathit{Q}}^{2}$=1.75 to 8.83 (GeV/c${)}^{2}$ via a Rosenbluth separation ep cross section measurements in the angular range 13\ifmmode^\circ\else\textdegree\fi{}\ensuremath{\le}\ensuremath{\theta}\ensuremath{\le}90\ifmmode^\circ\else\textdegree\fi{}. ${\mathit{Q}}^{2}$ covered more than doubles that of existing...
Separated longitudinal and transverse structure functions for the reaction 1H(e,e(')pi(+))n were measured in momentum transfer region Q2 = 0.6--1.6 (GeV/c)(2) at a value of invariant mass W 1.95 GeV. New values pion charge form factor extracted from cross section by using recently developed Regge model. The results indicate that this is larger than previously assumed consistent with monopole parametrization fitted to very low elastic data.
The neutron longitudinal and transverse asymmetries A1n A2n have been extracted from deep inelastic scattering of polarized electrons by a He3 target at incident energies 19.42, 22.66, 25.51 GeV. measurement allows for the determination spin structure functions g1n(x, Q2) g2n(x, over range 0.03<x<0.6 an average Q2 2 (GeV/c)2. data are used evaluation Ellis-Jaffe Bjorken sum rules. function is small negative within our measurement, yielding integral ∫0.030.6g1n(x)dx=−0.028±0.006 (stat)±0.006...
We report the results of a new Rosenbluth measurement proton electromagnetic form factors at Q2 values 2.64, 3.20, and 4.10 GeV2. Cross sections were determined by detecting recoiling proton, in contrast to previous measurements which detected scattered electron. 3%, with relative uncertainties below 1%. The ratio mu(p)G(E)/G(M) was 4%-8% showed approximately 1. These are consistent with, much more precise than, extractions. They inconsistent recent polarization transfer similar precision,...
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....
We report on precision measurements of the elastic cross section for electron-proton scattering performed in Hall C at Jefferson Lab. The were made 28 distinct kinematic settings covering a range momentum transfer $0.4<{Q}^{2}<5.5\phantom{\rule{0.3em}{0ex}}{(\mathrm{GeV}∕c)}^{2}$. These represent significant contribution to world's data set ${Q}^{2}$ range, where large discrepancy currently exists between ratio electric magnetic proton form factors extracted from previous and that recently...
The data analysis for the reaction H(e,e' pi^+)n, which was used to determine values charged pion form factor Fpi of Q^2=0.6-1.6 GeV^2, has been repeated with careful inspection all steps and special attention systematic uncertainties. Also method extract from measured longitudinal cross section critically reconsidered. Final separated transverse sections extracted are presented.
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 a study of muon neutrino charged-current quasi-elastic events in the segmented scintillator inner tracker MINERvA experiment running NuMI beam at Fermilab. The were selected by requiring {\mu}^- and low calorimetric recoil energy separated from interaction vertex. measure flux-averaged differential cross-section, d{\sigma}/dQ^2, particle content final state. Deviations are found between measured d{\sigma}/dQ^2 expectations model independent nucleons relativistic Fermi gas. also...
Quasielastic e-d cross sections have been measured at forward and backward angles. Rosenbluth separations were done to obtain ${\mathit{R}}_{\mathit{L}}$ ${\mathit{R}}_{\mathit{T}}$ ${\mathit{Q}}^{2}$=1.75, 2.50, 3.25, 4.00 (GeV/c${)}^{2}$. The neutron form factors ${\mathit{G}}_{\mathit{E}\mathit{n}}$ ${\mathit{G}}_{\mathit{M}\mathit{n}}$ extracted using a nonrelativistic model. sensitivity deuteron wave function, relativistic corrections, models of the inelastic background are reported....
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 isolated muon anti-neutrino charged-current quasi-elastic interactions occurring in the segmented scintillator tracking region of MINERvA detector running NuMI neutrino beam at Fermilab. measure flux-averaged differential cross-section, d{\sigma}/dQ^2, and compare to several theoretical models scattering. Good agreement is obtained with a model where nucleon axial mass, M_A, set 0.99 GeV/c^2 but vector form factors are modified account for observed enhancement, relative free case,...
Considerable evidence now exists to show that the relative biological effectiveness (RBE) changes considerably along proton depth-dose distribution, with progressively higher RBE values at distal part of modulated, or spread out Bragg peak (SOBP) and in dose fall-off (DDF). However, highly variable nature existing studies (with regards cell lines, physical properties dosimetry various beams) precludes any consensus regarding weighting factor position profile. We have thus conducted a...
We perform a global chi^2-analysis of nuclear parton distribution functions using data from charged current neutrino-nucleus deep-inelastic scattering (DIS), charged-lepton-nucleus DIS, and the Drell-Yan (DY) process. show that corrections in nu-A DIS are not compatible with predictions derived l^+A DY data. quantify this result hypothesis-testing criterion based on chi^2 which we apply to total as well individual sets. find it is possible accommodate by an acceptable combined fit. Our has...
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...
The ratio of the nucleon F_{2} structure functions, F_{2}^{n}/F_{2}^{p}, is determined by MARATHON experiment from measurements deep inelastic scattering electrons ^{3}H and ^{3}He nuclei. was performed in Hall A Facility Jefferson Lab using two high-resolution spectrometers for electron detection, a cryogenic target system which included low-activity tritium cell. data analysis used novel technique exploiting mirror symmetry nuclei, essentially eliminates many theoretical uncertainties...
We studied the electroproduction of $\ensuremath{\Delta}(1232)$ resonance via reaction $p({e,e}^{\ensuremath{'}}p){\ensuremath{\pi}}^{0}$ at four-momentum transfers ${Q}^{2}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}2.8\mathrm{and}4.0{\mathrm{GeV}}^{2}$. This is highest ${Q}^{2}$ for which exclusive has ever been observed. Decay angular distributions $\ensuremath{\Delta}\ensuremath{\rightarrow}p{\ensuremath{\pi}}^{0}$ were measured over a wide range barycentric energies covering...
We report new measurements of the ratio electric form factor to magnetic neutron, G(n)(E)/G(n)(M), obtained via recoil polarimetry from quasielastic 2H(e-->,e(')n-->)1H reaction at Q2 values 0.45, 1.13, and 1.45 (GeV/c)(2) with relative statistical uncertainties 7.6% 8.4% two higher points, which points have never been achieved in polarization measurements.