Measurement of the cross section for prompt isolated diphoton production in pp collisions at square root(s) = 1.96 TeV

Phys Rev Lett. 2011 Sep 2;107(10):102003. doi: 10.1103/PhysRevLett.107.102003. Epub 2011 Sep 2.

Abstract

This Letter reports a measurement of the cross section of prompt isolated photon pair production in pp collisions at a total energy square 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.