Beam-spin Asymmetries from Semi-inclusive Pion Electroproduction

Conference · Tue Oct 01 00:00:00 EDT 2013

OSTI ID:1989811

Gohn, Wesley ^[1]; Avakian, Harut ^[2]; Joo, Kyungseon ^[3]; Ungaro, Maurizio ^[2]

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1. Univ. of Kentucky, Lexington, KY (United States)
2. Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
3. Univ. of Connecticut, Storrs, CT (United States)

The moment of the semi-inclusive deep inelastic scattering (SIDIS) cross section corresponding to a polarized lepton scattering from an unpolarized target is Asin?LU. It has been extracted from measurements of beam-spin asymmetries (BSAs) from pion electro-production in SIDIS. Data were taken with the continuous electron beam accelerator facility (CEBAF) Large Acceptance Spectrometer (CLAS) at Jefferson Lab using a 5.498 GeV longitudinally polarized electron beam and an unpolarized liquid hydrogen target. All three pion channels (?+, ?0 and ??) were measured simultaneously over a large range of kinematics at the intermediate Q2 range (Q2? 1 - 4.5 GeV2). The moment is measured as functions of z, PT, x, and Q2. Asin?LU is a twist-3 structure providing information about quark-gluon-quark correlations. This new high statistical data will provide an important means of studying the transverse degrees of freedom in the nucleon.

• Research Organization: Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Nuclear Physics (NP)
• DOE Contract Number: AC05-06OR23177
• OSTI ID: 1989811
• Report Number(s): JLAB-PHY-14-2078; DOE/OR/23177-6712
• Resource Relation: Conference: 2013 Fall Meeting of the APS Division of Nuclear Physics, October 23–26, 2013, Newport News, Virginia
• Country of Publication: United States
• Language: English