Final-state interaction as origin of single-spin asymmetry in semi-inclusive DIS

Journal Article · Fri May 06 00:00:00 EDT 2005 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.1932925· OSTI ID:20718946

Hwang, D S ^[1]

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1. Department of Physics, Sejong University, Seoul 143-747 (Korea, Republic of)

Recent measurements from the HERMES, SMC, CLAS and COMPASS collaborations show a remarkably large azimuthal single-spin asymmetries of the proton in semi-inclusive pion leptoproduction {gamma}*(q)p{up_arrow} {yields} {pi}X. The existence of such single-spin asymmetries requires a phase difference between two amplitudes coupling the proton target with J{sub p}{sup z} = {+-}(1/2) to the same final-state, the same amplitudes which are necessary to produce a nonzero proton anomalous magnetic moment. We show that the exchange of gauge particles between the outgoing quark and the proton spectators produces a Coulomb-like complex phase which depends on the angular momentum Lz of the proton's constituents and is thus distinct for different proton spin amplitudes. We then find that final-state interactions from gluon exchange between the outgoing quark and the target spectator system lead to single-spin asymmetries at leading twist in perturbative QCD; i.e., the rescattering corrections are not power-law suppressed at large photon virtuality Q2 at fixed xbj.

• OSTI ID: 20718946
• Journal Information: AIP Conference Proceedings, Vol. 768, Issue 1; Conference: 19. European conference on few-body problems in physics, Groningen (Netherlands), 23-27 Aug 2004; Other Information: DOI: 10.1063/1.1932925; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
AMPLITUDES
ASYMMETRY
CORRECTIONS
COUPLING
DEEP INELASTIC SCATTERING
FINAL-STATE INTERACTIONS
GLUONS
MAGNETIC MOMENTS
MULTIPARTICLE SPECTROMETERS
PARTICLE PRODUCTION
PHOTON-PROTON INTERACTIONS
PHOTONS
PIONS
PROTONS
QUANTUM CHROMODYNAMICS
QUARKS
SEMI-INCLUSIVE INTERACTIONS
SPIN