Speaker
Federica Sozzi
(INFN)
Description
The study of transverse spin effects
is part of the scientific program of COMPASS,
a fixed target experiment at the CERN SPS.
COMPASS investigates the transversity PDF in semi-inclusive DIS,
using a longitudinally polarized muon beam of 160~GeV/c
impinging on transversely polarized nucleons.
From 2002 to 2004, a $^6$LiD target has been used;
in these data transversity has been measured using different
quark polarimeters: azimuthal distribution of single hadrons,
azimuthal dependence of the plane containing hadron pairs,
and measurement of transverse polarization of baryons
($\lambda$ hyperons).
All the asymmetries have been found to be small,
and compatible with zero,
a result that has been interpreted as cancellation
between the u and d-quark contribution in the deuteron.
Complementary information on transverse spin effects will be obtained analyzing the data taken by COMPASS
in 2007 using a NH$_3$ target.
Author
F Sozzi
(University and INFN Trieste)
