Speaker
Malte Christian Wilfert
(Johannes-Gutenberg-Universitaet Mainz (DE))
Description
The COMPASS experiment at CERN SPS has taken data with a polarised muon beam scattering off a polarised NH$_3$ target in 2011. The beam energy has been increased to 200 GeV compared to 160 GeV in 2007 and thus, higher values of $Q^2$ and lower values of $x$ are reached.
We will present our results on the longitudinal double spin asymmetry $A_1^p$ and the spin-dependent structure function $g_1^p$. These results are used in a NLO QCD fit to the world data to obtain the polarised parton distributions and also to update our results on the Bjorken sum rule, connecting the integral of the non-singlet structure function with the ratio of the weak coupling constants.
Supported by BMBF under the contract 05P12UMCC1 and GRK Symmetry Breaking (DFG/GRK 1581)
Primary author
Malte Christian Wilfert
(Johannes-Gutenberg-Universitaet Mainz (DE))
