This Letter reports a measurement of the cross section of prompt isolated photon pair production in p (p) over bar collisions at a total energy root s = 1.96 TeV using data of 5.36 fb(-1) integrated luminosity collected with the CDF II detector at the Fermilab Tevatron. The measured cross section, differential in basic kinematic variables, is compared with three perturbative QCD predictions, a leading order parton shower calculation and two next- to- leading order calculations. The next-to-leading order calculations reproduce most aspects of the data. By including photon radiation from quarks before and after hard scattering, the parton shower prediction becomes competitive with the next-to-leading order predictions. RI Robson, Aidan/G-1087-2011; De Cecco, Sandro/B-1016-2012; Prokoshin, Fedor/E-2795-2012
File in questo prodotto:
Non ci sono file associati a questo prodotto.