Status of the experimental studies on DVMP and transversity GPDs

Conference · Sat Sep 01 04:00:00 EDT 2018 · Proceedings of 23rd International Spin Physics Symposium — PoS(SPIN2018)

DOI:https://doi.org/10.22323/1.346.0075· OSTI ID:1969715

Kubarovsky, Valery

The cross section of the exclusive ?0 and ? electroproduction reaction ep?e?p??0/? was measured at Jefferson Lab with a 5.75-GeV electron beam and the CLAS detector. Differential cross sections d4?/dtdQ2dxBd? and structure functions ?U=?T+??L,?TT and ?LT , as functions of t were obtained over a wide range of Q2 and xB . At low t , both ?0 and ? are described reasonably well by Generalized Parton Distributions (GPDs) model in which chiral-odd transversity GPDs are dominant. Generalized form factors of the transversity GPDs H?,?T and E¯?,?T were directly extracted from the experimental observables. The combined ?0 and ? data opens the way for the flavor decomposition of the transversity GPDs. The first ever demonstration of this decomposition was done for the transversity GPDs HT and E¯T . GPD E¯T is connected with the density of the polarized quarks in an unpolarized nucleon in the impact parameter space. The spin density of polarized u and d -quarks was evaluated for different values of Feynman x from the GPD model tuned to described the experimental data.

• Research Organization: Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Nuclear Physics (NP)
• DOE Contract Number: AC05-06OR23177
• OSTI ID: 1969715
• Report Number(s): JLAB-PHY-19-3160; DOE/OR/23177-6034
• Conference Information: Journal Name: Proceedings of 23rd International Spin Physics Symposium — PoS(SPIN2018) Journal Volume: SPIN 2018
• Country of Publication: United States
• Language: English