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

0345111 - FZÚ 2011 RIV US eng J - Článek v odborném periodiku
Adare, A. - Afanasiev, S. - Aidala, C. - Růžička, Pavel - Tomášek, Lukáš - Vrba, Václav
Inclusive cross section and double helicity asymmetry for pi(0) production in p+p collisions at sqrt(s) = 62.4 GeV.
Physical Review D: Particles, Fields, Gravitation and Cosmology. Roč. 79, č. 1 (2009), 012003/1-012003/4. ISSN 1550-7998
Grant CEP: GA MŠMT LA08015
Výzkumný záměr: CEZ:AV0Z10100502
Klíčová slova: Phenix * double helicity asymmetry
Kód oboru RIV: BF - Elementární částice a fyzika vys. energií
Impakt faktor: 4.922, rok: 2009
http://arxiv.org/pdf/0810.0701

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.
Trvalý link: http://hdl.handle.net/11104/0186452