COMPASS results on Collins and Sivers asymmetries for charged hadrons

Understand

The study of transverse spin and transverse momentum effects is an important part of the scientific program of COMPASS, a fixed target experiment at the CERN SPS taking data since 2002.

• The studies are carried on by measuring the hadrons produced in deep inelastic scattering (DIS) of 160 GeV/c muons off different targets.
• Among the possible asymmetries in the hadron azimuthal distributions, particularly interesting are the Collins and Sivers asymmetries which the COMPASS Collaboration has measured using transversely polarised deuteron and proton targets.
• The new results for charged pions and kaons obtained from the 2010 run with a transversely polarised proton target are presented.