Early physics with the LHCf experiment at LHC

LHCf, the smallest of the LHC experiment, has been designed to study the forward production of neutral particles in proton-proton collisions at LHC. The aim of the experiment is to provide valuable information for the calibration of the nuclear interaction models used in the Monte Carlo codes developed for high and ultra-high energy cosmic ray Physics. These data are of extreme importance for the extraction of primary cosmic ray properties. In particular, since LHCf will take data already in the rst phase of operation of the LHC at 3.5+3.5 TeV up to the ultimate energy of 7+7 TeV, it will be able to span the most interesting energy range for high energy cosmic rays, above the “knee” region. To accomplish these precision measurements, LHCf is made of two double arm high precision calorimeters placed on both side of ATLAS interaction point. In this paper the performance of the LHCf detector will be discussed with particular emphasis to the early physics program.