Speaker
Christopher Braun
(Friedrich-Alexander-Univ. Erlangen (DE))
Description
For each quark flavour three independent parton distribution functions (PDF) are necessary to describe the nucleon at twist-two level, the quark distribution f1(x), the helicity distribution g1(x) and the transversity distribution h1(x). The transversity distribution function is chiral-odd and therefore is not accessible in deep inelastic scattering (DIS). However, h1(x) can be observed in semi-inclusive DIS in combination with another chirally odd function like the two-hadron interference fragmentation function (IFF) in two-hadron production, which is the subject of this contribution. The 160 GeV/c polarized µ+ beam of CERN's M2 beamline allows COMPASS to investigate the spin structure of the nucleon using polarized solid state targets. After taking the first data on a transversely polarized proton target NH3 in 2007, a full year of data taking followed in 2010 to increase precision. In this contribution the latest results from the 2010 data for the azimuthal asymmetries in two-hadron production are presented, as well as the corresponding results on a polarized deuteron target 6LiD from the data taken in the years 2002-2004. An extraction of h1(x) via a coupling to the two-hadron IFF has been carried out for the 2007 data.
Author
Christopher Braun
(Friedrich-Alexander-Univ. Erlangen (DE))