Scaling of single photon production in hadronic collisions

Abstract

Scaling of single photon production in $pp$ and $p\overline{p}$ collisions is studied. It is empirically observed the available data scales $\sim \sqrt{s}/p_T^5$ for $x_T=2p_T/\sqrt{s}\le 0.1$ and $\sim (\sqrt{s}{)}^{3.3}/p_T^9$ for larger $x_T$. The NLO pQCD predictions for $pp$ collisions at $\sqrt{s}$ of 200 and 5500 GeV, relevant for RHIC and LHC energies are seen to closely follow this scaling behaviour. Implications for single photon production in heavy ion collisions are discussed.

Comments: 4 pages including 5 figures. Figure 5 changed to include correct two-loop contributions. (Submitted to Eur. Phys. J. C.)