Abstract
The gluon polarization in the nucleon was measured using open charm production by scattering polarized muons off longitudinally polarized protons or deuterons. The data were taken by the COMPASS Collaboration between 2002 and 2007. A detailed account is given of the analysis method that includes the application of neural networks. Several decay channels of mesons are investigated. Longitudinal spin asymmetries of the D meson production cross sections are extracted in bins of transverse momentum and energy. At leading order QCD accuracy, the average gluon polarization is determined as at the scale and an average gluon momentum fraction . The average gluon polarization is also obtained at next-to-leading order QCD accuracy as at the scale and .
6 More- Received 28 November 2012
DOI:https://doi.org/10.1103/PhysRevD.87.052018
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