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 protonproton 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 pT(μ) > 4 GeV and pseudorapidity |η(μ)|< 2.1, a fit to the dimuon pT(μ⁺μ^-) distribution results in a measured cross section of σ(p→pμ⁺μ^-p) = 0.83^+0.14_-0.13 (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^+0.14_-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.