Date of Award
Program or Major
Doctor of Philosophy
Over the past several decades Jefferson Lab National Accelerator Facility has proven to be extremely successful in its endeavor to study the polarized structure of nucleons. Measurements of these nucleon structure functions have proven to be powerful tools in testing and understanding a number of effective theories of QCD. The neutron spin structure functions, g1n and g2n, and the proton spin structure function, g1p, have been measured to very high precision over a wide kinematic range. However, the second proton structure function, g2p, remained largely unmeasured. The primary goal of Jefferson Lab Hall A experiment E08-027 was to perform an inclusive measurement of the proton g2 structure function for the first time in the low momentum transfer range of 0.01 < Q2 < 0.13 GeV2. The experiment acquired data at Jefferson Lab in Hall A during February - May of 2012. Experiment E08-027 utilized a polarized frozen NH3 target and a polarized electron beam to examine inclusive eP scattering in the resonance region. Dynamic Nuclear Polarization was used to drive proton target polarizations to upwards of 70% at 5T and 15% at 2.5T for high statistics measurements of the double spin asymmetry. Using a convolution of the Bosted/Christy model and data for the unpolarized cross section contribution, the spin structure function g2p was extracted for two low Q2 bins. Results for the moments of these structure functions find reasonable agreement with chiPT predictions.
Badman, Tobias, "The Proton Spin Structure Function G2P at Low Momentum Transfer" (2017). Doctoral Dissertations. 2295.