Measurement of the Inelastic Proton-Proton Cross Section at ps = 13 TeV with the ATLAS Detector at the LHC

摘要: This Letter presents a measurement of the inelastic proton-proton cross section using 60 μb−1 of pp collisions at a center-of-mass energy s√ of 13 TeV with the ATLAS detector at the LHC. Inelastic interactions are selected using plastic scintillators in the forward region of the detector. A cross section of 68.2±1.5 mb is measured in the fiducial region ξ=M2X/s>10−6, where MX is the largest invariant mass of the two hadronic systems separated by the largest rapidity gap in the event. In this ξ range the scintillators are highly efficient. For diffractive events this corresponds to cases where at least one proton dissociates to a system with MX>13 GeV. The measured cross section is compared with a range of theoretical predictions. When extrapolated to the full phase space, a cross-section of 79.3±2.9 mb is measured, consistent with the inelastic cross section increasing with center-of-mass energy.