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arXiv · 1012.4601

ΔG/G results from the COMPASS experiment for Q^2 > 1 GeV^2, using high p_T hadrons

Luís Silva
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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 p_T 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 p_T hadron pairs in events with Q^2>1 GeV^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 x_G.

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Luís Silva. 2011-01-14. ΔG/G results from the COMPASS experiment for Q^2 > 1 GeV^2, using high p_T hadrons. https://doi.org/10.1088/1742-6596%2F295%2F1%2F012067

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