New measurements of $\Delta G/G$ at COMPASS

One of the main goals of the COMPASS experiment at CERN is the determination of the gluon polarisation in the nucleon, $\Delta G/G$. It is determined from spin asymmetries in the scattering of polarised muons at 160GeV/c on a polarised LiD target. The gluon polarisation is accessed by the selection of photon-gluon fusion events. Such events are tagged either with a charmed meson or a hadron pair with high transverse momenta in the final state. The selection of charmed mesons is based on the reconstruction of decayed $D^{*}$ and $D^{0}$ mesons in the COMPASS spectrometer. For the high-$p_{T}$ hadron pairs two independent analyses are performed in the kinematic regimes of DIS ($Q^{2} >$ 1 (GeV/c)$^{2}$) and quasi-real photoproduction ($Q^{2} <$ 1 $^{2}(GeV/c)$). The results presented in this paper were obtained from the data coming from 2002-2004 for the open charm and the high $p_{T}$ with $Q^{2} <$ 1 (GeV/c)$^{2}$ channels resp. from 2002-2003 for the high $p_{T}$ with Q$^{2} >$ 1 (GeV/c)$^{2}$ channel.