C. Gleason
A5061367344- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Nuclear physics research studies
- Atomic and Subatomic Physics Research
- Radiation Detection and Scintillator Technologies
- Particle Detector Development and Performance
- Advanced NMR Techniques and Applications
- Nuclear Physics and Applications
- Dark Matter and Cosmic Phenomena
- Medical Imaging Techniques and Applications
- Atomic and Molecular Physics
- X-ray Spectroscopy and Fluorescence Analysis
- Advancements in Photolithography Techniques
- Radiation Therapy and Dosimetry
- Advanced Chemical Physics Studies
- Radiation Shielding Materials Analysis
- Photoreceptor and optogenetics research
- Radioactivity and Radon Measurements
- Molecular Spectroscopy and Structure
- Particle Accelerators and Free-Electron Lasers
- Inorganic Fluorides and Related Compounds
- Algebraic and Geometric Analysis
- Photonic and Optical Devices
Union College
2022-2024
William & Mary
2024
Williams (United States)
2024
Indiana University Bloomington
2018-2023
Temple University
2022
George Washington University
2020
University of South Carolina
2016-2020
Thomas Jefferson National Accelerator Facility
2018
Istituto Nazionale di Fisica Nucleare, Sezione di Ferrara
2017
University of Bonn
2017
We report on the measurement of γp→J/ψp cross section from E_{γ}=11.8 GeV down to threshold at 8.2 using a tagged photon beam with GlueX experiment. find that total falls toward less steeply than expected two-gluon exchange models. The differential dσ/dt has an exponential slope 1.67±0.39 GeV^{-2} 10.7 average energy. LHCb pentaquark candidates P_{c}^{+} can be produced in s channel this reaction. see no evidence for them and set model-dependent upper limits their branching fractions...
We report the total and differential cross sections for $J/\psi$ photoproduction with large acceptance GlueX spectrometer photon beam energies from threshold at 8.2~GeV up to 11.44~GeV over full kinematic range of momentum transfer squared, $t$. Such coverage facilitates extrapolation forward ($t = 0$) point beyond physical region. The section is used by many theoretical models plays an important role in understanding its relation $J/\psi-$proton interaction. These measurements near are also...
Background: The electromagnetic form factors of the proton measured by unpolarized and polarized electron scattering experiments show a significant disagreement that grows with squared four-momentum transfer $({Q}^{2})$. Calculations have shown two measurements can be largely reconciled accounting for contributions two-photon exchange (TPE). TPE effects are not typically included in standard set radiative corrections since theoretical calculations highly model dependent, and, until recently,...
Background: Measurements of polarization observables for the reactions $\stackrel{P\vec}{\ensuremath{\gamma}}p\ensuremath{\rightarrow}{K}^{+}\mathrm{\ensuremath{\Lambda}}$ and $\stackrel{P\vec}{\ensuremath{\gamma}}p\ensuremath{\rightarrow}{K}^{+}{\mathrm{\ensuremath{\Sigma}}}^{0}$ have been performed. This is part a program measurements designed to study spectrum baryon resonances in particular, nonperturbative QCD general.Purpose: The accurate measurement several provides tight constraints...
The basic properties of the proton, lightest baryon, are determined by its quark and gluon composition. In particular, spin $\mathrm{\ensuremath{\Elzxh}}/2$ has been a challenge to understand in terms proton's constituents. comprehensive results presented here based on measurements with high precision dense kinematic coverage carried out CLAS detector at Jefferson Lab. They provide new insight into proton substructure resolutions length scale whole nucleon down level. A variety strong...
We measure for the first time differential photoproduction cross section $d\sigma/dt$ of $a_2(1320)$ meson at an average photon beam energy 8.5~GeV, using data with integrated luminosity 104~pb$^{-1}$ collected by GlueX experiment. fully reconstruct $\gamma p \to \eta\pi^0 p$ reaction and perform a partial-wave analysis in mass region amplitudes that incorporate linear polarization beam. This allows us to separate contributions natural- unnatural-parity exchanges. These measurements provide...
We report on the first measurement of beam-spin asymmetry in exclusive process coherent deeply virtual Compton scattering off a nucleus. The experiment uses 6 GeV electron beam from Continuous Electron Beam Accelerator Facility (CEBAF) accelerator at Jefferson Lab incident pressurized ^{4}He gaseous target placed front CEBAF Large Acceptance Spectrometer (CLAS). scattered is detected by CLAS and photon dedicated electromagnetic calorimeter forward angles. To ensure exclusivity process,...
Measurements of the linearly-polarized photon beam asymmetry Σ for photoproduction from proton η and η′ mesons are reported. A tagged produced by coherent bremsstrahlung was incident on a cryogenic hydrogen target within CEBAF Large Acceptance Spectrometer. Results presented γp→ηp reaction energies 1.070 to 1.876 GeV, 1.516 1.836 GeV γp→η′p reaction. For γp→ηp, data reported here considerably extend range measurements higher energies, consistent with few previously published this observable...
This paper reports new exclusive cross sections for $e p \to e' \pi^+ \pi^- p'$ using the CLAS detector at Jefferson Laboratory. These results are presented first time photon virtualities 2.0 GeV^2 < Q^2 5.0 in center-of-mass energy range 1.4 GeV W GeV, which covers a large part of nucleon resonance region. Using model developed phenomenological analysis electroproduction data, we see strong indications that relative contributions from resonant 1.74 increase with $Q^2$. data considerably...
We present a search for axionlike particles, $a$, produced in photon-proton collisions at center-of-mass energy of approximately 4 GeV, focusing on the scenario where $a$-gluon coupling is dominant. The uses $a\ensuremath{\rightarrow}\ensuremath{\gamma}\ensuremath{\gamma}$ and $a\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}$ decays, data sample corresponding to an integrated luminosity $168\text{ }\text{...
We report the first measurement of differential and total cross sections for $\ensuremath{\gamma}d\ensuremath{\rightarrow}{K}^{0}\mathrm{\ensuremath{\Lambda}}(p)$ reaction, using data from CLAS detector at Thomas Jefferson National Accelerator Facility. Data collected during two separate experimental runs were studied with photon-energy coverage 0.8--3.6 GeV 0.5-- 2.6 GeV, respectively. The measurements are consistent giving confidence in method determination systematic uncertainties....
We report the first beam-target double-polarization asymmetries in γ+n(p)→π^{-}+p(p) reaction spanning nucleon resonance region from invariant mass W=1500 to 2300 MeV. Circularly polarized photons and longitudinally deuterons solid hydrogen deuteride (HD) have been used with CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. The exclusive final state has extracted using three very different analyses that show excellent agreement, these deduce E polarization observable for an...
We propose to create a secondary beam of neutral kaons in Hall D at Jefferson Lab be used with the GlueX experimental setup for strange hadron spectroscopy. The superior CEBAF electron will enable flux on order $1\times 10^4~K_L/sec$, which exceeds that previously attained SLAC by three orders magnitude. use deuteron target provide first measurements ever neutrons. experiment measure both differential cross sections and self-analyzed polarizations produced $Λ$, $Σ$, $Ξ$, $Ω$ hyperons using...
The quasifree γd→π−p(p) differential cross section has been measured with CLAS at photon beam energies Eγ from 0.445 to 2.510 GeV (corresponding W 1.311 2.366 GeV) for pion center-of-mass angles cosθc.m.π −0.72 0.92. A correction final state interactions applied these data extract the γn→π−p sections. These sections are quoted in 8428 (Eγ,cosθc.m.π) bins, a factor of nearly 3 increase world statistics this channel kinematic range. new help constrain coupled-channel analysis fits used...
The cross section of the exclusive $\ensuremath{\eta}$ electroproduction reaction $ep\ensuremath{\rightarrow}{e}^{\ensuremath{'}}{p}^{\ensuremath{'}}\ensuremath{\eta}$ was measured at Jefferson Laboratory with a 5.75 GeV electron beam and CLAS detector. Differential sections ${d}^{4}\ensuremath{\sigma}/dtd{Q}^{2}d{x}_{B}d{\ensuremath{\phi}}_{\ensuremath{\eta}}$ structure functions...
We report a new measurement of the beam-spin asymmetry $\boldsymbol{\Sigma}$ for $\vec{\gamma} n \rightarrow K^+\Sigma^-$ reaction using quasi-free neutrons in liquid-deuterium target. The dataset includes data at previously unmeasured photon energy and angular ranges, thereby providing constraints on partial wave analyses used to extract properties excited nucleon states. experimental were obtained CEBAF Large Acceptance Spectrometer (CLAS), housed Hall B Thomas Jefferson National...
The reaction ⁎γp→K⁎+Λ was measured using the CLAS detector for photon energies between threshold and 3.9 GeV at Thomas Jefferson National Accelerator Facility. For first time, spin-density matrix elements have been extracted this reaction. Differential cross sections, spin density elements, Λ recoil polarization are compared with theoretical predictions BnGa partial wave analysis. main result is evidence significant contributions from N(1895)1/2− N(2100)1/2+ to Branching ratios decays into...
We report on the measurement of beam asymmetry $\mathrm{\ensuremath{\Sigma}}$ for reactions $\stackrel{P\vec}{\ensuremath{\gamma}}p\ensuremath{\rightarrow}p\ensuremath{\eta}$ and $\stackrel{P\vec}{\ensuremath{\gamma}}p\ensuremath{\rightarrow}p{\ensuremath{\eta}}^{\ensuremath{'}}$ from GlueX experiment using an 8.2--8.8-GeV linearly polarized tagged photon incident a liquid hydrogen target in Hall D at Jefferson Laboratory. These measurements are made as function momentum transfer...
The double-polarization observable E was studied for the reaction γp→pω using CEBAF Large Acceptance Spectrometer (CLAS) in Hall B at Thomas Jefferson National Accelerator Facility and longitudinally polarized frozen-spin target (FROST). measured from charged decay mode of meson, ω→π+π−π0, a circularly tagged-photon beam with energies ranging ω threshold 1.1 to 2.3 GeV. A partial-wave analysis within Bonn-Gatchina framework found dominant contributions 3/2+ partial wave near threshold, which...
The GlueX experiment at Jefferson Lab studies photoproduction of mesons using linearly polarized 8.5GeV photons impinging on a hydrogen target which is contained within detector with near-complete coverage for charged and neutral particles. We present measurements spin-density matrix elements the vector meson ρ(770). statistical precision achieved exceeds that previous experiments in this energy range by orders magnitude. confirm high degree s-channel helicity conservation small squared...
This paper reports the measurement of polarized and unpolarized cross sections for ep -> e'p' reaction, which is comprised Deeply Virtual Compton Scattering (DVCS) Bethe-Heitler (BH) processes, at an electron beam energy 5.88 GeV Thomas Jefferson National Accelerator Facility using Large Acceptance Spectrometer CLAS. The section differences have been measured over broad kinematics, 0.10 < x_B 0.58, 1.0 Q^2 4.8 GeV^2, 0.09 -t 2.00 GeV^2. results are found to be consistent with previous CLAS...