Measurements of exclusive dilepton production at 7 and 8 TeV with the ATLAS detector

In the absence of forward proton tagging, exclusive processes can be distinguished in the central part of the ATLAS detector exploiting the large rapidity gap in the central region and the absence of charged particles reconstructed in the inner tracking detector. This strategy has been exploited to study the exclusive production of dilepton pairs in the data taken at centre­of­mass energies of 7 and 8 TeV. A measurement of exclusive production of dileptons (ee and mumu) in 7 TeV pp collisions is presented. The results show significant deviations from the pure QED prediction, which can be explained by photon coherence and proton rescattering effects. A new analysis performed at 8 TeV concentrates on the emu final state to search for the exclusive production of WW boson pairs. Furthermore the analysis is re­optimised to search for the exclusive production of the Higgs boson in the WW* decay channel.