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تسجيل مستخدم جديدInclusive cross section and double helicity asymmetry for pi^0 production in p+p collisions at sqrt(s) = 62.4 GeV
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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 measurements are presented for the cross section and double-helicity asymmetry ($A_{LL}$) in inclusive $pi^0$ production at midrapidity from $p$$+$$p$ collisions at $sqrt{s}=510$~GeV from data taken in 2012 and 2013 at the Relativistic Heavy I
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