Exclusive γγ → μ + μ − production in proton-proton collisions at √s=7 TeV

Abstract

A measurement of the exclusive two-photon production of muon pairs in proton-proton collisions at s√=7 TeV, pp → pμ + μ −p, is reported using data corresponding to an integrated luminosity of 40 pb−1. For muon pairs with invariant mass greater than 11.5 GeV, transverse momentum p T (μ) > 4 GeV and pseudorapidity |η(μ)| < 2.1, a fit to the dimuon p T (μ + μ −) distribution results in a measured cross section of σ(p → pμ + μ −p) = 3.38+0.58−0.55 (stat.) ± 0.16 (syst.) ± 0.14 (lumi.) pb, consistent with the theoretical prediction evaluated with the event generator Lpair. The ratio to the predicted cross section is 0.83+0.58−0.13 (stat.) ± 0.04 (syst.) ± 0.03 (lumi.). The characteristic distributions of the muon pairs produced via γγ fusion, such as the muon acoplanarity, the muon pair invariant mass and transverse momentum agree with those from the theory.