Speaker
Mr
Malte Wilfert
(Johannes-Gutenberg-Universitaet Mainz)
Description
The COMPASS experiment at CERN SPS has taken data with a polarised muon beam scattering off a polarised LiD target from 2002-2004. The same measurement was also performed in 2006 increasing the statistics by roughly a factor of two.
The new results from 2006 data on the longitudinal double spin asymmetry A_1^d on the spin dependent structure function g_1^d will be shown and compared to the previous results from 2002-2004. Using the combined data set the first moment of g_1^d is calculated. This quantity is used to calculate the singlet axial charge a_0, which is equal to Delta Sigma in the MSbar scheme. Using also the axial charges a_3 and a_8 the first moments of the quark helicity distributions are obtained. In addition the influence on the Bjorken sum rule will be discussed.
Supported by BMBF and GRK Symmetry Breaking (DFG/GRK 1581)
Primary author
Mr
Malte Wilfert
(Johannes-Gutenberg-Universitaet Mainz)
