Measurement of the total cross section from elastic scattering in pp collisions at View the MathML sources=8 TeV with the ATLAS detector

A measurement of the total pp cross section at the LHC at View the MathML sources=8 TeV is presented. An integrated luminosity of 500 µb-1500 µb-1 was accumulated in a special run with high-ß?ß? beam optics 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 0.014 GeV20.014 GeV2 to 0.1 GeV20.1 GeV2 to extrapolate t?0t?0, the total cross section, stot(pp?X)stot(pp?X), is measured via the optical theorem to be View the MathML sourcestot(pp?X)=96.07±0.18(stat.)±0.85(exp.)±0.31(extr.)mb, where the first error is statistical, the second accounts for all experimental systematic uncertainties and the last is related to uncertainties in the extrapolation t?0t?0. In addition, the slope of the exponential function describing the elastic cross section at small t is determined to be View the MathML sourceB=19.74±0.05(stat.)±0.23(syst.)GeV-2.