Longitudinal double-spin asymmetries of inclusive jet and dijet production at STAR

Journal Article · Tue Jul 12 00:00:00 EDT 2022 · SciPost Physics Proceedings

DOI:https://doi.org/10.21468/SciPostPhysProc.8.086· OSTI ID:1875932

Zurek, Maria ^[1]

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1. Argonne National Laboratory

The STAR experiment probes the gluon helicity distribution \Delta g(x, Q^2) $\Delta g(x,Q^2)$ using collisions of longitudinally polarized protons at \sqrt{s} = 200 $\sqrt{s}=200$ ~GeV and \sqrt{s} = 510 $\sqrt{s}=510$ ~GeV. \Delta g(x, Q^2) $\Delta g(x,Q^2)$ can be accessed through the double-spin asymmetries A_{LL} $A_{LL}$ in gluon-dominated hard scattering processes via inclusive jet and dijet production. This proceedings report on recent measurements of A_{LL} $A_{LL}$ for inclusive jets and dijets in the mid-pseudorapidity ( |\eta| < 1 $\left|\eta \right|<1$ ) and dijets in the intermediate pseudrapidity ( -0.8 < \eta < 1.8 $-0.8<\eta <1.8$ ) regions. These measurements provide sensitivity to \Delta g(x, Q^2) $\Delta g(x,Q^2)$ for gluon momentum fractions x $x$ from \simeq 0.5 $\simeq 0.5$ down to \simeq 0.004 $\simeq 0.004$ . The results are in good agreement with previous STAR measurements and recent theoretical evaluations of prior world data.

• Sponsoring Organization: USDOE
• OSTI ID: 1875932
• Journal Information: SciPost Physics Proceedings, Journal Name: SciPost Physics Proceedings Journal Issue: 8; ISSN 2666-4003
• Publisher: Stichting SciPost
• Country of Publication: Netherlands
• Language: English