Measurement of the Cross Section for Prompt Isolated Diphoton Production in p\bar p Collisions at \sqrt{s} = 1.96 TeV

TL;DR

This paper measures the production rate of prompt isolated photon pairs in proton-antiproton collisions at 1.96 TeV, comparing results with various QCD calculations to evaluate their accuracy in describing the data.

Contribution

First measurement of diphoton production cross section at Tevatron energies, with detailed comparison to multiple QCD theoretical predictions.

Findings

All theoretical models capture main features of the data.

No model fully describes all aspects of the measured cross section.

Results highlight the need for improved QCD calculations.

Abstract

This article reports a measurement of the production cross section of prompt isolated photon pairs in proton-antiproton collisions at \sqrt{s} = 1.96 TeV using the CDF II detector at the Fermilab Tevatron collider. The data correspond to an integrated luminosity of 5.36/fb. The cross section is presented as a function of kinematic variables sensitive to the reaction mechanisms. The results are compared with three perturbative QCD calculations: (1) a leading order parton shower Monte Carlo, (2) a fixed next-to-leading order calculation and (3) a next-to-leading order/next-to-next-to-leading-log resummed calculation. The comparisons show that, within their known limitations, all calculations predict the main features of the data, but no calculation adequately describes all aspects of the data.