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arXiv · hep-ex/0612055

Measurements of Delta G/G

G. K. Mallot
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Abstract

Our present information on the gluon polarisation Delta g/g is reviewed. The data from fixed-target lepton-nucleon experiments are in context with the recent data from the RHIC polarised pp collider. The main tools to study Delta g/g in lepton-nucleon scattering are scaling violations of the g_1 structure functions and longitudinal spin asymmetries in hadron production. Results from high-p_T hadron pairs, inclusive hadrons as well as open-charm production are discussed. At RHIC the most precise data presently came from inclusive pi^0 and jet production. All data indicate that the gluon polarisation is small compared to earlier expectations, but still can make a major contribution to the nucleon spin.

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G. K. Mallot. 2006-12-22. Measurements of Delta G/G. https://doi.org/10.1063/1.2750788

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