Measurement of P-T-weighted Sivers asymmetries in leptoproduction of hadrons

0508852 - ÚPT 2020 RIV NL eng J - Journal Article
Alexeev, M. - Alexeev, G. D. - Amoroso, A. - Srnka, Aleš … Total 224 authors
Measurement of P-T-weighted Sivers asymmetries in leptoproduction of hadrons.
Nuclear Physics. B. Roč. 940, MAR (2019), s. 34-53. ISSN 0550-3213. E-ISSN 1873-1562
Institutional support: RVO:68081731
Keywords : transverse-spin asymmetries * deep-inelastic scattering
OECD category: Nuclear physics
Impact factor: 2.817, year: 2019
Method of publishing: Open access
https://reader.elsevier.com/reader/sd/pii/S055032131830364X?token=F910543B9BE642E0FDCAB02A1EF3E52EEB560E4D393B7D059E559C9B38C35FCDB0D18FD1DE6EF5D19832151B0CF69A41

The transverse spin asymmetries measured in semi-inclusive leptoproduction of hadrons, when weighted with the hadron transverse momentum P-T, allow for the extraction of important transverse-momentum-dependent distribution functions. In particular, the weighted Sivers asymmetries provide direct information on the Sivers function, which is a leading-twist distribution that arises from a correlation between the transverse momentum of an unpolarised quark in a transversely polarised nucleon and the spin of the nucleon. Using the high-statistics data collected by the COMPASS Collaboration in 2010 with a transversely polarised proton target, we have evaluated two types of P-T-weighted Sivers asymmetries, which are both proportional to the product of the first transverse moment of the Sivers function and of the fragmentation function. The results are compared to the standard unweighted Sivers asymmetries and used to extract the first transverse moments of the Sivers distributions for u and d quarks.
Permanent Link: http://hdl.handle.net/11104/0299651