Transverse-Target-Spin Asymmetry in Exclusive {omega}-Meson Electroproduction

Journal Article · Thu Dec 17 00:00:00 EST 2015 · European Physical Journal. C, Particles and Fields

DOI:https://doi.org/10.1140/epjc/s10052-015-3825-7· OSTI ID:1239106

Airapetian, A.; Akopov, N.; Akopov, Z.; Aschenauer, E. C.; Augustyniak, W.; Avetissian, A.; Belostotski, S.; Blok, H. P.; Borissov, A.; Bryzgalov, V.; Jackson, H. E.; Reimer, P. E.

Hard exclusive electroproduction of omega mesons is studied with the HERMES spectrometer at the DESY laboratory by scattering 27.6 GeV positron and electron beams off a transversely polarized hydrogen target. The amplitudes of five azimuthal modulations of the single-spin asymmetry of the cross section with respect to the transverse proton polarization are measured. They are determined in the entire kinematic region as well as for two bins in photon virtuality and momentum transfer to the nucleon. Also, a separation of asymmetry amplitudes into longitudinal and transverse components is done. These results are compared to a phenomenological model that includes the pion pole contribution. Within this model, the data favor a positive pi omega transition form factor.

• Research Organization: Argonne National Lab. (ANL), Argonne, IL (United States)
• Sponsoring Organization: USDOE Office of Science - Office of Nuclear Physics
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 1239106
• Journal Information: European Physical Journal. C, Particles and Fields, Vol. 75, Issue 12; ISSN 1434-6044
• Publisher: Springer
• Country of Publication: United States
• Language: English