Sivers Asymmetries for Inclusive Pion and Kaon Production in Deep-Inelastic Scattering

Abstract

We calculate the Sivers distribution functions induced by the final-state interaction due to one-gluon exchange in diquark models of nucleon structure, treating the cases of scalar and axial-vector diquarks with both dipole and Gaussian form factors. We use these distribution functions to calculate the Sivers single-spin asymmetries for inclusive pion and kaon production in deep-inelastic scattering. We compare our calculations with the results of HERMES and COMPASS, finding good agreement for pi+ production at HERMES, and qualitative agreement for pi0 and K+ production. Our predictions for pion and kaon production at COMPASS could be probed with increased statistics. The successful comparison of our calculations with the HERMES data constitutes prima facie evidence that the quarks in the nucleon have some orbital angular momentum in the infinite-momentum frame.

31 pages, 14 figures

References in corpus (5)

• Global analysis of fragmentation functions for pions and kaons and their uncertainties
• Transverse-momentum distributions in a diquark spectator model
• Sivers Effect for Pion and Kaon Production in Semi-Inclusive Deep Inelastic Scattering
• Transverse Quark Spin Effects and the Flavor Dependence of the Boer-Mulders Function
• HERMES measurements of Collins and Sivers asymmetries from a transversely polarised hydrogen target

Cited by in corpus (1)

• Naive time-reversal odd phenomena in semi-inclusive deep-inelastic scattering from light-cone constituent quark models