Longitudinal double-spin asymmetries for π<SUP>0</SUP>s in the forward direction for 510 GeV polarized <i>pp</i> collisions



Adam, J, Adamczyk, L, Adams, JR, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Ajitanand, NN, Alekseev, I, Anderson, DM
et al (show 338 more authors) (2018) Longitudinal double-spin asymmetries for π<SUP>0</SUP>s in the forward direction for 510 GeV polarized <i>pp</i> collisions. PHYSICAL REVIEW D, 98 (3). 032013-.

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Abstract

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, $\Delta g(x)$, down to the region of Bjorken $x \sim 10^{-3}$. The asymmetries observed are less than $\pm 5 \cdot 10^{-3}$ 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.

Item Type: Article
Uncontrolled Keywords: hep-ex, hep-ex, nucl-ex
Depositing User: Symplectic Admin
Date Deposited: 07 May 2019 10:14
Last Modified: 10 Oct 2023 23:23
DOI: 10.1103/PhysRevD.98.032013
Open Access URL: https://doi.org/10.1103/PhysRevD.98.032013
Related URLs:
URI: https://livrepository.liverpool.ac.uk/id/eprint/3040048