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arXiv · 1109.3310

Measurement of the Production Cross Section of Pairs of Isolated Photons with CMS

Laurent Millischer
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Abstract

In this paper we present the measurement of the integrated and differential production cross sections of pairs of prompt isolated photons in proton-proton collisions at a centre-of-mass energy of 7 TeV with the Compact Muon Sollenoid (CMS) detector at the Large Hadron Collider (LHC). A next-to-leading order (NLO) perturbative QCD (pQCD) prediction was compared to the measurement, which was performed on a sample corresponding to an integrated luminosity of 36 inverse picobarn. While the agreement on integrated cross sections is satisfactory, a discrepancy is observed in the region of the phase space populated by photons with small relative angle, where the theoretical prediction underestimates the measured cross section.

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Laurent Millischer. 2011-09-15. Measurement of the Production Cross Section of Pairs of Isolated Photons with CMS. https://arxiv.org/abs/1109.3310

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