Year of Publication
Doctor of Philosophy (PhD)
Arts and Sciences
Physics and Astronomy
Dr. Wolfgang Korsch
The neutron, although electrically neutral, is composed of elementary charged particles and as a result, possesses a charge distribution within. The charge distribution can be studied by measuring a quantity called the neutron electric form factor, GnE. Experiment E02-013 at Jefferson Lab’s Hall A measured GnE at high four-momentum transfer values of Q2 = 1.2, 1.7, 2.5 and 3.4 (GeV/c)2 in double polarized semi-exclusive 3He(e, e'n) scattering in quasi-elestic kinematics by measuring the transverse asymmetry AT of the cross section.
The neutron electric form factor is essential to know for a variety of reasons. Results from the recent Jefferson Lab experiment on the proton revealed interesting features at these momentum transfers, whereas no accurate data for the neutron is available. Also the recent development in Generalized Parton Distributions (GPDs) necessitates the need for precise values for GnE in Q2 range between 1 and 10 (GeV/c)2; they appear as limiting conditions for certain GPD functions, for example, to constrain spin-flip GPDs. The experiment used the polarized 3He target and the polarized CEBAF electron beam at energies of about 1.52, 2.08, 2.64 and 3.29 GeV. The electrons were detected in the BigBite spectrometer and the neutrons in a large array of scintillators in coincidence with the electrons.
In this dissertation, we report a preliminary result, GnE = 0.03457 ± 0.007239 at Q2 = 1.7 (GeV/c)2.
Kolarkar, Ameya Suresh, "PRECISION MEASUREMENTS OF THE NEUTRON ELECTRIC FORM FACTOR AT HIGH MOMENTUM TRANSFERS" (2008). University of Kentucky Doctoral Dissertations. 612.