Publications
Publication Information
Title | Deep Exclusive p0 Electroproduction Measured in Hall A at Jefferson Lab with the Upgraded CEBAF |
Authors | Bishnu Karki |
JLAB number | JLAB-PHY-20-3268 |
LANL number | (None) |
Other number | DOE/OR/23177-5073 |
Document Type(s) | (Thesis) |
Associated with EIC: | No |
Supported by Jefferson Lab LDRD Funding: | No |
Funding Source: | Nuclear Physics (NP) |
Thesis A PHD thesis Advisor(s) : Julie Roche (Ohio University) | |
Publication Abstract: | Our understanding of the proton?s structure in terms of its fundamental degrees of freedom, quarks and gluons, is incomplete. Generalized Parton Distributions (GPDs) can enhance our understanding of the partonic structure of the proton as it includes the correlation between the momentum and transverse position of partons. Exclusive electroproduction of the pion (ep->e'p'p^0) is one of the potential channels to access the GPDs. GPDs are defined at the Bjorken limit where the total amplitude can be factorized in a hard scattering of the photon off the quark and a soft part described by the GPDs. At sufficiently high Q2, a factorization scheme for exclusive meson production processes exists but only for longitudinally polarized virtual photons. As long as the longitudinally polarized virtual photons dominate the cross-section, we can have factorization and extract the GPDs. But the existing data for p^0 production at low Q2 and low xB show the dominance of transverse part of the cross-section over the longitudinal one. Some transversity GPD models have found that an effective way to factorize the contribution from transversely polarized virtual photons to explain the dominance of s_T over s_L, shown by existing data. The experiment E12-06-114 ran in experimental Hall A during 2014-2016. The primary goal of this experiment was to measure the DVCS cross-section but the experimental configuration also allows the measurement of deep exclusive p^0 production. Taking advantage of the upgraded CEBAF at Jefferson Lab, we explored the high Bjorken-x (0.60) and high Q2 regime for the first time. The extracted cross-section terms for p^0 production helps us to test the validity of QCD factorization in our kinematic regime. Our p^0 production results can be used to test and improve the existing models of proton structure. Cross-section results will be presented at two di?erent Q2 values for fixed xB of 0.60. |
Experiment Numbers: | E12-06-114 |
Group: | Hall A |
Document: | |
DOI: | |
Accepted Manuscript: | |
Supporting Documents: | |
Supporting Datasets: |