Proton opacity in the light of LHC diffractive data

Abstract

We show that collider data on elastic pp (and p\bar{p}) scattering, including the LHC TOTEM data at 7 TeV, can be well described by a 3-channel eikonal model with only one Pomeron, with parameters that are naturally linked to the perturbative QCD (BFKL) framework. The proton opacity, determined in this way, is then used to account for sizeable absorptive effects. We study the recent measurements of dσ/dΔηmade by the ATLAS collaboration, where they select events with large rapidity gaps Δη. We demonstrate that the absorptive corrections noticeably change both the value and the Δηdependence of the cross section. We find that our parameter-free calculation is in agreement with these ATLAS data.

17 pages, 6 figures. Version to be published in EPJC