Speaker
Isabella Garzia
(INFN Ferrara)
Description
Transversity Distribution, which describes the quark transverse polariza- tion inside a transversely polarized nucleon, is the last leading-twist miss- ing piece of the QCD description of the partonic structure of the nucleon. Transversity can be extracted from semi-inclusive deep inelastic scattering data, where it couples to a new, unknown fragmentation function, called Collins function. We present a measurement of the azimuthal asymmetries in the process e+e− → pipiX (inclusive hadron production), in which the two pions are produced in opposite hemispheres, based on the full BABAR data sample. The Collins function is extracted from the measured asymmetries.
