A measurement of the total pp cross section at the LHC at √{ s} = 7 TeV is presented. In a special run with high-β⋆ beam optics, an integrated luminosity of 80 μb-1 was accumulated in order to measure the differential elastic cross section as a function of the Mandelstam momentum transfer variable t. The measurement is performed with the ALFA sub-detector of ATLAS. Using a fit to the differential elastic cross section in the | t | range from 0.01 GeV2 to 0.1 GeV2 to extrapolate to | t | → 0, the total cross section, σtot (pp → X), is measured via the optical theorem to be:

Aad, G., Abbott, B., Abdallah, J., Abdel Khalek, S., Abdinov, O., Aben, R., et al. (2014). Measurement of the total cross section from elastic scattering in pp collisions at √s=7 TeV with the ATLAS detector. NUCLEAR PHYSICS. B, 889, 486-548 [10.1016/j.nuclphysb.2014.10.019].

Measurement of the total cross section from elastic scattering in pp collisions at √s=7 TeV with the ATLAS detector

V. Bortolotto;F. Ceradini;B. Di Micco;R. Di Nardo;D. Orestano;F. Petrucci;D. Puddu;G. Salamanna;