Speaker
Dr
Luis Silva
(LIP Lisbon)
Description
In the context of the nucleon spin structure, the contribution from the gluons plays an important role. The so-called gluon polarisation can be determined in DIS through the Photon-Gluon Fusion (PGF) process. In the COMPASS experiment, data were collected with a naturally polarised 160 GeV/c muon beam, impinging on a polarised nucleon. Two analyses aiming at the extraction of the gluon polarisation were performed. One is based on the identification of open charm events and the other on the selection of events with high-p_T hadrons.
The final results for the gluon polarisation from these analyses were obtained in LO approximation. For the open charm data an analysis in NLO was performed. In the case of high-p_T events, for the first time, the results are extracted in 3 x_g bins. Also A^{2h} asymmetries were recently evaluated in 2-Dim bins of x and pT^2. In both analyses, a weighted method based on a neural network approach is used.
Author
Dr
Luis Silva
(LIP Lisbon)
