Forward photon energy spectrum at LHC 7 TeV p–p collisions measured by LHCf

The LHCf experiment is one of the LHC forward experiments. The aim is to measure the energy and the transverse momentum spectra of photons, neutrons and π0π0's at the very forward region (the pseudo-rapidity range of η>8.4η>8.4), which should be critical data to calibrate hadron interaction models used in the air shower simulations. LHCf successfully operated at s=900GeV and s=7TeV proton–proton collisions in 2009 and 2010. We present the first physics result, single photon energy spectra at s=7TeV proton–proton collisions and the pseudo-rapidity ranges of η>10.94η>10.94 and 8.81<η<8.98.81<η<8.9. The obtained spectra were compared with the predictions by several hadron interaction models and the models do not reproduce the experimental results perfectly.