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Measurement of the gluon polarization ΔG/G at COMPASS

C. Schill
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Abstract

One of the key objectives of the COMPASS experiment at CERN is the determination of the gluon contribution to the nucleon spin. The gluon polarization is measured via photon-gluon fusion in deep-inelastic scattering of 160 GeV/c polarized muons on a polarized 6LiD solid-state target. Photon-gluon fusion is tagged by the observation of charmed mesons or the production of hadron pairs with large transverse momenta p_t. The status of the analysis of the D0 and D0* events and of the high-p_t hadron pairs is shown. The gluon polarization ΔG/G has been determined from the asymmetry of high-p_t hadron pairs with Q^2>1 GeV/c^2 in an analysis of the 2002/03 data as ΔG/G=0.06 \pm 0.31 (stat.) \pm 0.06 (syst.).

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C. Schill. 2005-01-21. Measurement of the gluon polarization ΔG/G at COMPASS. https://doi.org/10.1142/9789812701909_0041

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