M. Hattawy
A5107868446- Quantum Chromodynamics and Particle Interactions
- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Nuclear physics research studies
- Particle Detector Development and Performance
- Dark Matter and Cosmic Phenomena
- Atomic and Subatomic Physics Research
- Particle Accelerators and Free-Electron Lasers
- Advanced NMR Techniques and Applications
- Atomic and Molecular Physics
- Pulsars and Gravitational Waves Research
- Radiation Detection and Scintillator Technologies
- Advanced Chemical Physics Studies
- Scientific Research and Discoveries
- Astronomical and nuclear sciences
- Particle accelerators and beam dynamics
- High-pressure geophysics and materials
- Computational Physics and Python Applications
- Inorganic Fluorides and Related Compounds
- Machine Learning in Materials Science
- Molecular Spectroscopy and Structure
- Medical Imaging Techniques and Applications
- Quantum, superfluid, helium dynamics
- Radiation Therapy and Dosimetry
- Superconducting Materials and Applications
Old Dominion University
2018-2025
Dominion University College
2025
Thomas Jefferson National Accelerator Facility
2017-2024
University of California, Riverside
2024
Istituto Nazionale di Fisica Nucleare, Sezione di Genova
2017-2024
Argonne National Laboratory
2015-2023
Duquesne University
2020-2023
Istituto Nazionale di Fisica Nucleare, Roma Tor Vergata
2023
Justus-Liebig-Universität Gießen
2022
SLAC National Accelerator Laboratory
2022
The atomic nucleus is composed of two different kinds fermions, protons and neutrons. If the neutrons did not interact, Pauli exclusion principle would force majority fermions (usually neutrons) to have a higher average momentum. Our high-energy electron scattering measurements using 12C, 27Al, 56Fe 208Pb targets show that, even in heavy neutron-rich nuclei, short-range interactions between form correlated high-momentum neutron-proton pairs. Thus, greater probability than momentum Fermi This...
Unpolarized and beam-polarized fourfold cross sections (d^{4}σ/dQ^{2}dx_{B}dtdϕ) for the ep→e^{'}p^{'}γ reaction were measured using CLAS detector 5.75-GeV polarized electron beam of Jefferson Lab accelerator, 110 (Q^{2},x_{B},t) bins over widest phase space ever explored in valence-quark region. Several models generalized parton distributions (GPDs) describe data well at most our kinematics. This increases confidence that we understand GPD H, expected to be dominant contributor these...
Much less is known about neutron structure than that of the proton due to absence free targets. Neutron information usually extracted from data on nuclear targets such as deuterium, requiring corrections for binding and nucleon off-shell effects. These are model dependent have significant uncertainties, especially large values Bjorken scaling variable x. The Barely Off-shell Nucleon Structure (BONuS) experiment at Jefferson Lab measured inelastic electron deuteron scattering cross section,...
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...
High-statistics measurements of differential cross sections and spin density matrix elements for the reaction $\ensuremath{\gamma}p\ensuremath{\rightarrow}\ensuremath{\phi}p$ have been made using CLAS detector at Jefferson Lab. We cover center-of-mass energies ($\sqrt{s}$) from 1.97 to 2.84 GeV, with an extensive coverage in $\ensuremath{\phi}$ production angle. The high statistics data sample it necessary carefully account interplay between natural lineshape effects resolution, that are...
Single-beam, single-target, and double-spin asymmetries for hard exclusive photon production on the proton $\vec{e}\vec{p} \to e' p'\gamma$ are presented. The data were taken at Jefferson Lab using CLAS detector a longitudinally polarized ${}^{14}$NH$_3$ target. three measured in 165 4-dimensional kinematic bins, covering widest range ever explored simultaneously beam target-polarization observables valence quark region. dependences of obtained discussed compared to predictions models...
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...
Differential cross sections of the exclusive process $ep\ensuremath{\rightarrow}{e}^{\ensuremath{'}}{\ensuremath{\pi}}^{+}n$ were measured with good precision in range photon virtuality ${Q}^{2}=1.8--4.5$ ${\mathrm{GeV}}^{2}$ and invariant mass ${\ensuremath{\pi}}^{+}n$ final state $W=1.6--2.0$ GeV using Continuous Electron Beam Accelerator Facility Large Acceptance Spectrometer. Data collected nearly complete coverage azimuthal polar angles $n{\ensuremath{\pi}}^{+}$ center-of-mass system....
A measurement of the electroproduction photons off protons in deeply inelastic regime was performed at Jefferson Lab using a nearly 6 GeV electron beam, longitudinally polarized proton target, and CEBAF Large Acceptance Spectrometer. Target-spin asymmetries for ep→e^{'}p^{'}γ events, which arise from interference virtual Compton scattering Bethe-Heitler processes, were extracted over widest kinematics Q^{2}, x_{B}, t, ϕ, 166 four-dimensional bins. In framework generalized parton...
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...
Exclusive neutral-pion electroproduction ($ep\to e^\prime p^\prime \pi^0$) was measured at Jefferson Lab with a 5.75-GeV electron beam and the CLAS detector. Differential cross sections $d^4\sigma/dtdQ^2dx_Bd\phi_\pi$ structure functions $\sigma_T+\epsilon\sigma_L, \sigma_{TT}$ $\sigma_{LT}$ as of $t$ were obtained over wide range $Q^2$ $x_B$. The data are compared Regge handbag theoretical calculations. Analyses in both frameworks find that large dominance transverse processes is necessary...
We present the final results for deuteron spin structure functions obtained from full data set collected with Jefferson Lab's CLAS in 2000-2001. Polarized electrons energies of 1.6, 2.5, 4.2 and 5.8 GeV were scattered ($^{15}$ND$_3$) targets, dynamically polarized along beam direction, detected CLAS. From measured double asymmetry, virtual photon absorption asymmetry $A_1^d$ function $g_1^d$ extracted over a wide kinematic range (0.05 GeV$^2 < Q^2 <$ 5 GeV$^2$ 0.9 $< W 3 GeV). use an...
High-momentum configurations of nucleon pairs at short-distance are probed using measurements the $^{12}$C$(e,e'p)$ and $^{12}$C$(e,e'pN)$ reactions (where $N$ is either $n$ or $p$), high-$Q^2$ $x_B>1.1$. The data span a missing-momentum range 300--1000 MeV/c predominantly sensitive to transition region strong nuclear interaction from Tensor Scalar interaction. well reproduced by theoretical calculations Generalized Contact Formalism with both chiral phenomenological nucleon-nucleon...
Strange matter is believed to exist in the cores of neutron stars based on simple kinematics. If this true, then hyperon-nucleon interactions will play a significant part star equation state (EOS). Yet, compared other elastic scattering processes, there very little data $\Lambda$-$N$ scattering. This experiment utilized CLAS detector study $\Lambda p \rightarrow \Lambda p$ cross section incident $\Lambda$ momentum range 0.9-2.0 GeV/c. first reaction several decades. The new sections have...
Background: Energetic quarks in nuclear DIS propagate through the medium. Processes that are believed to occur inside nuclei include quark energy loss medium-stimulated gluon bremsstrahlung and intra-nuclear interactions of forming hadrons. More data required gain a more complete understanding these effects. Purpose: To test theoretical models parton transport hadron formation, we compared their predictions for kinematic dependence pion production nuclei. Methods: We have measured...
A multidimensional extraction of the structure function ratio σLT′/σ0 from hard exclusive e→p→e′nπ+ reaction above resonance region has been performed. The study was done based on beam-spin asymmetry measurements using a 10.6 GeV incident electron beam liquid-hydrogen target and CLAS12 spectrometer at Jefferson Lab. focus very forward regime (t/Q2 ≪ 1) with wide kinematic range xB in valence (0.17 < 0.55), virtualities Q2 ranging 1.5 GeV2 up to 6 GeV2. results their comparison theoretical...
We report the first measurements of deep inelastic scattering spin-dependent azimuthal asymmetries in back-to-back dihadron electroproduction process. In this reaction, two hadrons are produced opposite hemispheres along z axis virtual photon-target nucleon center-of-mass frame, with hadron current-fragmentation region and second target-fragmentation region. The data were taken longitudinally polarized electron beams 10.2 10.6 GeV incident on an unpolarized liquid-hydrogen target using...
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,...
Results are presented for the first measurement of double-polarization helicity asymmetry E $η$ photoproduction reaction $γp \rightarrow ηp$. Data were obtained using FROzen Spin Target (FROST) with CLAS spectrometer in Hall B at Jefferson Lab, covering a range center-of-mass energy W from threshold to 2.15 GeV and large polar angle. As an initial application these data, results have been incorporated into Jülich model examine case existence narrow $N^*$ resonance between 1.66 1.70 GeV. The...