Assessing signals of TMD physics in SIDIS azimuthal asymmetries and in the extraction of the Sivers function

Boglione M;D'Alesio U;Flore C;Gonzalez H. O.

2018-01-01

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Abstract

New data on the Sivers azimuthal asymmetry measured in semi-inclusive deepinelastic scattering processes have recently been released by the COMPASS Collaboration at CERN. Their increased precision and their particular binning, in terms of Q2as well as x, motivates a new extraction of the Sivers function, within the framework of a simple and transparent parametrization. Signals of TMD effects visible in the Sivers asymmetries are critically assessed. A thorough study of the uncertainties affecting the extracted Sivers function is presented, including the low- and large-x regions.