Understanding the role of Cahn and Sivers effects in Deep Inelastic Scattering

Journal Article · Thu Oct 06 04:00:00 EDT 2005 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.2122202· OSTI ID:20726610

Anselmino, M; Boglione, M; Prokudin, A ^[1]; D'Alesio, U; Murgia, F ^[2]; Kotzinian, A ^[3]; Yerevan, AM-375036 ^[4]

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1. Dipartimento di Fisica Teorica, Universita di Torino, Sezione di Torino, Via P. Giuria 1, I-10125 Turin (Italy)
2. INFN, Sezione di Cagliari, Universita di Cagliari, C.P. 170, I-09042 Monserrato (Canada) (Italy)
3. Dipartimento di Fisica Generale, Universita di Torino, Sezione di Torino, Via P. Giuria 1, I-10125 Turin (Italy) and INFN, Sezione di Torino, Via P. Giuria 1, I-10125 Turin (Italy) and Yerevan Physics Institute, Alikhanian Brothers St. 2
4. Armenia

The role of intrinsic k perpendicular in semi-inclusive Deep Inelastic Scattering (SIDIS) processes (lp {yields} lhX) is studied with exact kinematics within QCD parton model at leading order; the dependence of the unpolarized cross section on the azimuthal angle between the leptonic and the hadron production planes (Cahn effect) is compared with data and used to estimate the average values of k perpendicular both in quark distribution and fragmentation functions. The resulting picture is applied to the description of the weighted single spin asymmetry A{sub UT}{sup sin({phi}{sub {pi}}{sup -{phi}}{sub S})} recently measured by the HERMES collaboration at DESY; this allows to extract parameters for the quark Sivers functions. The extracted Sivers functions give predictions for the COMPASS measurement of A{sub UT}{sup sin({phi}{sub {pi}{sup -{phi}}{sub S})} in agreement with recent data, while their contribution to HERMES A{sub UL}{sup sin{phi}{sub {pi}}} is computed and found to be small. Predictions for A{sub UT}{sup sin({phi}{sub K}{sup -{phi}}{sub S})} for kaon production at HERMES are also given.

• OSTI ID: 20726610
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 792; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ASYMMETRY
CROSS SECTIONS
DEEP INELASTIC SCATTERING
DESY
DISTRIBUTION
MULTIPARTICLE SPECTROMETERS
PARTICLE IDENTIFICATION
PARTICLE PRODUCTION
QUANTUM CHROMODYNAMICS
QUARK MODEL
QUARKS
SEMI-INCLUSIVE INTERACTIONS
SPIN