ΔG/G results from the COMPASS experiment for Q2 > 1 (GeV/c)2 using high pT hadrons

Abstract

One of the goals of COMPASS experiment is the determination of the gluon polarisation, ΔG/G, for a deep understanding of the spin structure of the nucleon. The gluon polarisation can be measured via the Photon-Gluon-Fusion (PGF) process. One of the methods to identify this process is selecting high pT hadron pairs in the final state. The data used for this analysis were collected by the COMPASS experiment during the years 2002 to 2006, using a 160 GeV naturally polarised positive muon beam impinging on a polarised nucleon target. A new result of ΔG/G from high pT hadron pairs in events with Q2 > 1 (GeV/c)2 is presented. This result has a better precision due to the addition of 2006 data and an improved analysis based on a neural network approach. The gluon polarisation is also presented in three bins of xG.