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

A preliminary measurement of the total pp cross section at the LHC at $\sqrt{s}$=7TeV is presented in this talk. In a special run with high betastar beam optics corresponding to an integrated luminosity of 80 inverse microbarn elastic scattering is measured in thwe range from -t=0.0025 GeV$^{2}$ to -t=0.38 GeV$^{2}$ with the ALFA subdetector of ATLAS. From the extrapolation of the differential elastic cross section to t=0 GeV$^{2}$ using the Optical Theorem the total cross section $\sigma(pp\rightarrow X)$ is extracted with the luminosity-dependent method. In addition the nuclear slope of the elastic t-spectrum, the total elastic and inelastic cross sections are determined.