Longitudinal double-spin asymmetries for pi(0)s in the forward direction for 510 GeV polarized pp collisions

0493324 - ÚJF 2019 RIV US eng J - Journal Article
Adam, J. - Adamczyk, L. - Adams, J. R. - Adkins, J. K. - Agakishiev, G. - Aggarwal, M. M. - Bielčík, J. - Bielčíková, Jana - Chaloupka, P. - Federič, Pavol - Federičová, P. - Harlenderová, A. - Holub, L. - Kramárik, L. - Kvapil, J. - Lidrych, J. - Matonoha, O. - Rusňák, Jan - Rusňáková, O. - Šimko, Miroslav - Šumbera, Michal - Vaněk, Jan … Total 349 authors
Longitudinal double-spin asymmetries for pi(0)s in the forward direction for 510 GeV polarized pp collisions.
Physical Review D. Roč. 98, č. 3 (2018), č. článku 032013. ISSN 2470-0010. E-ISSN 2470-0029
R&D Projects: GA MŠMT EF16_013/0001569
Institutional support: RVO:61389005
Keywords : STAR collaboration * transverse momenta * polarized gluons
OECD category: Nuclear physics
Impact factor: 4.368, year: 2018

The STAR Collaboration reports measurements of the longitudinal double-spin asymmetry, A(LL), for neutral pions produced at forward directions in polarized proton-proton collisions, at a center-of-mass energy of 510 GeV. Results are given for transverse momenta in the range 2 < p(T) < 10 GeV= c within two regions of pseudorapidity that span 2.65 < eta < 3.9. These results are sensitive to the polarized gluon parton distribution function, Delta g(chi) down to the region of Bjorken x similar to 10(-3). The asymmetries observed are less than similar to 5 x 10(-3) in magnitude and will help constrain the contribution to the spin of the proton from polarized gluons at low x, when combined with other measurements as part of a global analysis.
Permanent Link: http://hdl.handle.net/11104/0286702