Ratio of the Isolated Photon Cross Sections at \sqrt{s} = 630 and 1800 GeV

TL;DR

This paper measures the ratio of isolated photon production cross sections at two different energies in proton-antiproton collisions, comparing results with QCD predictions to test theoretical models.

Contribution

It provides the first measurement of the ratio of isolated photon cross sections at  and 1800 GeV, combining experimental data to evaluate QCD predictions.

Findings

Measured cross section ratio at two energies

Good agreement with next-to-leading order QCD in most energy ranges

Provides data for testing QCD models at different energies

Abstract

The inclusive cross section for production of isolated photons has been measured in \pbarp collisions at $\sqrt{s} = 630$ GeV with the \D0 detector at the Fermilab Tevatron Collider. The photons span a transverse energy ($E_T$) range from 7-49 GeV and have pseudorapidity $|\eta| < 2.5$. This measurement is combined with to previous \D0 result at $\sqrt{s} = 1800$ GeV to form a ratio of the cross sections. Comparison of next-to-leading order QCD with the measured cross section at 630 GeV and ratio of cross sections show satisfactory agreement in most of the $E_T$ range.