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arXiv · 0810.0701

Inclusive cross section and double helicity asymmetry for pi^0 production in p+p collisions at sqrt(s) = 62.4 GeV

PHENIX Collaboration·A. Adare
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Abstract

The PHENIX experiment presents results from the RHIC 2006 run with polarized proton collisions at sqrt(s) = 62.4 GeV for inclusive pi^0 production at mid-rapidity. Unpolarized cross section results are measured for transverse momenta p_T = 0.5 to 7 GeV/c. Next-to-leading order perturbative quantum chromodynamics calculations are compared with the data, and while the calculations are consistent with the measurements, next-to-leading logarithmic corrections improve the agreement. Double helicity asymmetries A_LL are presented for p_T = 1 to 4 GeV/c and probe the higher range of Bjorken_x of the gluon (x_g) with better statistical precision than our previous measurements at sqrt(s)=200 GeV. These measurements are sensitive to the gluon polarization in the proton for 0.06 < x_g < 0.4.

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PHENIX Collaboration, A. Adare. 2008-10-03. Inclusive cross section and double helicity asymmetry for pi^0 production in p+p collisions at sqrt(s) = 62.4 GeV. https://doi.org/10.1103/physrevd.79.012003

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