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Longitudinal Double Spin Asymmetry in Inclusive Jet Production at STAR

Katarzyna Kowalik
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Abstract

This contribution reports on the first measurement of the longitudinal double-spin asymmetry $A_{LL}$ for the inclusive production of jets in polarized proton-proton collisions at $\sqrt{s}=200 \mathrm{GeV}$. The data were collected with STAR at RHIC in the years 2003 and 2004, and correspond to a sampled integrated luminosity of $0.3 \mathrm{pb}^{-1}$ with beam polarizations up to 45%. The results on $A_{LL}$ cover jet transverse momenta $5 < p_{T} < 17 \mathrm{GeV/c}$ and agree with perturbative QCD evaluations based on deep-inelastic scattering parametrizations for the gluon polarization in the proton. The results disfavor large positive gluon polarization in the polarized proton.

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Katarzyna Kowalik. 2006-10-02. Longitudinal Double Spin Asymmetry in Inclusive Jet Production at STAR. https://doi.org/10.1063/1.2402723

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