Early physics results of the LHCf experiment

The LHCf experiment at LHC has been designed to calibrate the hadron interaction models used in High Energy Cosmic Ray (HECR) Physics through the measurement of the forward neutral particle produced in p-p interaction. The uncertainty caused by the poor knowledge of the interaction between very high energy primary cosmic ray and the earth's atmosphere prevents the precise deduction of astrophysical parameters from the observational data those causing the most important source of systematic error in HECR dedicated experiments. A calibration of the energy scale in the 10¹⁵ ÷ 10¹⁷ eV energy range accessible to LHC provides crucial input for a better interpretation of primary cosmic ray properties. In this paper, the status of the LHCf experiment with special emphasis to the first Physics results is discussed.