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Title: Polarization Transfer in Wide-Angle Compton Scattering and Single-Pion Photoproduction from the Proton

Journal Article · · Physical Review Letters

Wide-angle exclusive Compton scattering and single-pion photoproduction from the proton have been investigated via measurement of the polarization transfer from a circularly polarized photon beam to the recoil proton. The WACS polarization transfer was analyzed at an incident photon energy of 3.7 GeV at a proton scattering angle of θPcm = 70°. The longitudinal transfer KLL, measured to be 0.645 ± 0.059 ± 0.048, where the first error is statistical and the second is systematic, has the same sign as predicted for the reaction mechanism in which the photon interacts with a single quark carrying the spin of the proton. However, the observed value is ~3 times larger than predicted by the GPD-based calculations, which indicates a significant unknown contribution to the scattering amplitude.

Research Organization:
Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Nuclear Physics (NP)
Contributing Organization:
Jefferson Lab Hall C Collaboration
Grant/Contract Number:
AC05-84ER40150
OSTI ID:
1226145
Alternate ID(s):
OSTI ID: 1223139
Report Number(s):
JLAB-PHY-15-2059; DOE/OR/23177-3372; arXiv:1506.04045; PRLTAO
Journal Information:
Physical Review Letters, Vol. 115, Issue 15; ISSN 0031-9007
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 8 works
Citation information provided by
Web of Science

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