Physics Commons^™

Short Range Correlation Measurements In The Quasielastic Region With An 11 Gev Beam, Casey Morean

Doctoral Dissertations

Electron scattering is a significant means of studying internal high momentum
nucleon and quark distributions in nuclei. Thomas Jefferson National Accelerator
Facility (JLab) with its 11GeV beam is capable of studying high momentum nucleons
with unmatched precision. The role of short range nucleon configurations and
quark distributions is significant for understanding the dynamics of nuclei and their
underlying components. Scattering cross section measurements in the kinematic
regime x > 1, where the free nucleon is forbidden, are sensitive to high momentum
nucleons, which are believed to come from short range correlations (SRCs). SRCs are
strongly interacting, high momentum nucleons with a …

Nuclear Transparency From Quasi-Elastic $^{12}C(E,E'P)$ Scattering Reaction Up To $Q^2=14.2 ~(Gev/C)^{2}$ In Hall C At Jefferson Lab, Deepak Kumar Bhetuwal

Theses and Dissertations

Color Transparency $(CT)$ is a unique prediction of Quantum Chromodynamics $(QCD)$ where the final (and/or initial) state interactions of hadrons with the nuclear medium are suppressed for exclusive processes at high momentum transfers. While this phenomenon has been observed for mesons, there has never been a conclusive observation for baryons. A clear signal of $CT$ for baryons would be the first evidence of baryons fluctuating to a small size in the nucleus, and the onset would show the transition from nucleon-meson picture to quark-gluon degrees of freedom. The experiment $E1206107$, searching for the onset of $CT$ in protons was completed …

Spectator Proton Detection And Reconstruction In Deep Inelastic D(E,EpS) Scattering, David Payette

Physics Theses & Dissertations

A Radial Time Projection Chamber (RTPC) was designed and installed in Jefferson Lab's Hall B as part of the BONuS12 (Barely Off-shell Nucleon Structure) experiment. The goal of BONuS12 is to accurately measure the structure function of the neutron by scattering 11 GeV electrons and detecting them with the CLAS12 spectrometer. Deuterium gas was used as an effective neutron target, and the new RTPC was used to detect low- momentum spectator protons. Protons follow a curved path in the 5 Tesla solenoid that is part of CLAS12, ionizing the He-CO2 gas in an annular drift region surrounding the target. These …

Simulation And Development Of The Radial Time Projection Chamber For The Bonus12 Experiment In Clas12, Nathan M. Dzbenski

Physics Theses & Dissertations

Knowledge of the structure of nucleons (i:e: protons and neutrons) is a central topic of interest to nuclear/particle physicists. Much more is known about the structure of the proton than the neutron due to the lack of high-density free neutron targets. The Barely Off-shell Nucleon Structure experiment (BONuS12) at Jefferson Lab (JLab) is a second generation experiment upgraded/optimized to advance our knowledge of the neutron's structure using the deep-inelastic scattering of electrons off deuterium. Typically, since deuterium is a nuclear target, corrections for off-shell and nuclear binding effects must be taken into account in order to extract results on the …

Cross Section Measurements Of Deuteron Electro-Disintegration At Very High Recoil Momenta And Large 4-Momentum Transfers (Q2), Carlos Yero

FIU Electronic Theses and Dissertations

The ²H(e,e′p)n cross sections have been measured at negative 4-momentum transfers of Q² = 4.5±0.5 (GeV/c)² and Q² = 3.5±0.5 (GeV/c)² reaching neutron recoil (missing) momenta up to p_r ∼1.0 GeV/c. The data have been obtained at fixed neutron recoil angles 5^o ≤ θ_nq ≤ 95^o with respect to the 3-momentum transfer q. The new data agree well with the previous data which reached p_r ∼ 500 MeV/c. At θ_nq = 35^o and 45^o, final state interactions (FSI), meson exchange currents (MEC) and isobar configurations (IC) …

Monitoring Software And Charged Particle Identification For The Clas12 Detector, William A. Oliver

Theses and Dissertations

The CEBAF Large Acceptance Spectrometer for the 12 GeV era, known as CLAS12, uses the time of flight (TOF) system to identify charged particles from scattering events between the beam and target. The TOF system is divided into two parts: The Forward time of flight system, and the Central time of flight system. These two sub-systems subtend different polar angles of the detector geometry for wide acceptance of scattered particles. Reconstruction is the service used to identify particles from the interactions between the beam and target, called as a vertex or the point where the interaction occurs. The vertex position …

First Measurement Of The Ti(E, É) X Cross Section At Jefferson Lab, Jefferson Lab Hall A Collaboration, F. Hauenstein, C. Hyde

Physics Faculty Publications

To probeCPviolation in the leptonic sector usingGeVenergy neutrino beams in current and future experiments using argon detectors, precise models of the complex underlying neutrino and antineutrino interactions are needed. The E12-14-012 experiment at JeffersonLab HallAwas designed to perform a combined analysis of inclusive and exclusive electron scatterings on both argon (N = 22) and titanium (Z = 22) nuclei using GeV-energy electron beams. Themeasurement on titanium nucleus provides essential information to understand the neutrino scattering on argon, large contribution to which comes from scattering off neutrons. Here we report the first experimental study of electron-titanium scattering as double-differential cross section …

Crab Cavity Requirements For The Jefferson Lab Electron-Ion Collider, Salvador Isaac Sosa Güitrón

Physics Theses & Dissertations

An Electron-Ion Collider (EIC) has been proposed to be the next large facility to explore the dynamics of quarks and gluons inside nuclei. A conceptual design for a Jefferson Lab Electron-Ion Collider (JLEIC) is being developed. It is based on the CEBAF 12 GeV machine as a full energy electron beam injector. Two crucial requirements of JLEIC are high luminosity in the 10³⁴ cm^-2s^-1 range, and full acceptance detection of particles. The full acceptance requirement relies on having the beams collide at a relatively large crossing angle of 50 mrad. Such a large crossing angle, however, …

Searching For Heavy Photons With Detached Vertices In The Heavy Photon Search Experiment, Holly Szumila-Vance

Physics Theses & Dissertations

The Jefferson Lab Heavy Photon Search (HPS) experiment is searching for a hypothetical massive particle called the heavy photon which could mediate a dark electromagnetic-type force. If heavy photons kinetically mix with Standard Model photons, they may be radiated by electrons scattering from a heavy nucleus and then decay to e+e- pairs. HPS uniquely searches for heavy photons that either decay at the target or a measurable distance after. The experiment utilizes a silicon vertex tracker (SVT) for momentum and vertex reconstruction, together with an electromagnetic calorimeter for measuring particle energies and triggering events. The HPS experiment took its first …

First Measurement Of Unpolarized Semi-Inclusive Deep-Inelastic Scattering Cross Sections From A He 3 Target, X. Yan, K. Allada, K. Aniol, J. R. M. Annand, T. Averett, F. Benmokhtar, W. Bertozzi, P. C. Bradshaw, P. Bosted, A. Camsonne, M. Canan

Physics Faculty Publications

The unpolarized semi-inclusive deep-inelastic scattering (SIDIS) differential cross sections in ³He(e,e′π^±)X have been measured for the first time in Jefferson Lab experiment E06-010 with a 5.9GeV e- beam on a ³He gas target. The experiment focuses on the valence quark region, covering a kinematic range 0.12<x_bj<0.45,1<Q²<4(GeV/c)²,0.45<z_h<0.65, and 0.05<P_t<0.55GeV/c. The extracted SIDIS differential cross sections of π^± production are compared with existing phenomenological models while the ³He nucleus approximated as two protons and one neutron in a plane-wave picture, in multidimensional bins. Within …

The Gluex Start Counter & Beam Asymmetry $\Sigma$ In Single $\Pi^{0}$ Photoproduction, Eric J. Pooser

FIU Electronic Theses and Dissertations

The GlueX experiment aims to study meson photoproduction while utilizing the coherent bremsstrahlung technique to produce a 9 GeV linearly polarized photon beam incident on a liquid $\mathrm{H_{2}}$ target. A Start Counter detector was fabricated to properly identify the accelerator electron beam buckets and to provide accurate timing information. The Start Counter detector was designed to operate at photon intensities of up to $\mathrm{10^{8}\gamma/s}$ in the coherent peak and provides a timing resolution $\mathrm{\sim 300\ ps}$ so as to provide successful identification of the electron beam buckets to within 99\% accuracy. Furthermore, the Start Counter detector provides excellent solid angle …

Spectroscopy Of Li-9 (Lambda) By Electroproduction, G. M. Urciuoli, D. Hayes, C. E. Hyde, H. F. Ibrahim, P.E. Ulmer, Jefferson Lab Hall A Collaboration

Physics Faculty Publications

Background: In the absence of accurate data on the free two-body hyperon-nucleon interaction, the spectra of hypernuclei provides information on the details of the effective hyperon-nucleon interaction.

Purpose: To obtain a high-resolution binding-energy spectrum for the ⁹Be(e, e' K⁺)⁹_ΛLi reaction.

Method: Electroproduction of the hypernucleus ⁹_ΛLi has been studied for the first time with sub-MeV energy resolution in Hall A at Jefferson Lab on a ⁹Be target. In order to increase the counting rate and to provide unambiguous kaon identification, two superconducting septum magnets and a ring imaging Cherenkov detector were …

Measurement Of The Parity Violating Asymmetry In Elastic Electron Scattering Off 208pb, Jonathan W. Wexler

Doctoral Dissertations

The Lead Radius Experiment (PREX) was carried out in order to provide a model independent measurement of the RMS radius √ < r² >of the neutron distribution in the ²⁰⁸Pb nucleus. The parity-violating scattering asymmetry for longitudinally polarized 1.06 GeV electrons from an unpolarized ²⁰⁸Pb target was measured at Q² = 0.00880 GeV². This measurement was performed by the PREX collaboration in Hall A at Jefferson Laboratory in Newport News, VA, between March and June, 2010. The electron detectors used in this measurement were designed and fabricated by University of Massachusetts-Amherst and Smith College. The resulting …

Implementation Of The Clas12 Htcc Into Gemc, Nathan A. Harrison

Master's Theses

No abstract provided.