Speaker
Umberto D'Alesio
(Dipartimento di Fisica, Cagliari University)
Description
We present a global analysis of azimuthal asymmetries in e^+e^- -> h_1 h_2 X
processes (BELLE data) and in semi-inclusive deep inelasticscattering (HERMES and
COMPASS data). It results in the extraction of the Collins fragmentation function and
of the transversity distribution function for u and d quarks. Theseturn out to have
opposite signs and to be sizably smaller than their
positivity bounds. Predictions for the azimuthal asymmetry A_{UT}^{\in(phi_h + phi_S)
for polarized proton target at JLAB and COMPASS experiments are give
Author
Umberto D'Alesio
(Dipartimento di Fisica, Cagliari University)
