Investigations of azimuthal asymmetry
LNF-INFN, C.P. 13, Enrico Fermi 40, Frascati, Italy (e-mail: firstname.lastname@example.org, email@example.com, firstname.lastname@example.org, email@example.com)
Received: 24 October 1997 / Revised version: 10 February 1998 / Published online: 26 March 1998
We consider the azimuthal asymmetries in semi-inclusive deep inelastic leptoproduction arising due to both perturbative and nonperturbative effects at HERMES energies and show that the kT2/Q2 order corrections to and are significant. We also reconsider the results of perturbative effects for at large momentum transfers  using the more recent sets of scale-dependent distribution and fragmentation functions, which bring up to difference in . In the same approach we calculate the as well.