On the azimuthal asymmetries in DIS
A. V. Efremov, M. Polyakov, K. Goeke, D. Urbano
TL;DR
The paper addresses how to access the proton transversity distribution h1(x) in deep inelastic scattering by analyzing azimuthal asymmetries in semi-inclusive DIS. It employs the effective chiral quark-soliton model to predict h1 and uses DELPHI constraints on the T-odd fragmentation function H1_perp to compute observable asymmetries without free parameters, achieving good agreement with HERMES and SMC data. The study demonstrates that transversity can be probed in DIS with longitudinal targets through Wandzura-Wilczek-type relations and highlights the role of the Collins fragmentation mechanism. These results support future experiments, such as COMPASS, in measuring transversity alongside other spin observables, provided better constraints on the analyzing power are obtained.
Abstract
Using the recent experimental data on the left right asymmetry in fragmentation of transversely polarized quarks and the theoretical calculation of the proton transversity distribution in the effective chiral quark soliton model we explain the azimuthal asymmetries in semi-inclusive hadron production on longitudinal (HERMES) and transversely (SMC) polarized targets with no free parameters. On this basis we state that the proton transversity distribution could be successfully measured in future DIS experiments with longitudinally polarized target.