The multi-sources M. C. collision generator GHOST for C R simulations at LHC energies

Abstract

An extension of the model HDPM of CORSIKA has been developed taking the opportunity of the measurements performed presently by CMS, LHCb, TOTEM ... The new model GHOST involving a 4-source production is presented here. It reproduces correctly the pseudo-rapidity distributions of charged secondaries and can help the approach of the inclusive and semi-inclusive data in the mid and forward rapidity region, especially in the complex case of TOTEM. An important enhancement of both mean multiplicity and central pseudorapidity density is pointed out. Short range extrapolations up to √ s = 13 TeV suggest important consequences in the interpretation of cosmic ray measurements up to 10 17 eV. In parallel, simulation of cascades and EAS are also carried out in order to understand unexpected results in energy distributions of very high energy γ's, collected with X-ray emulsion chambers. If confirmed by the present and next measurements of the LHC at √ s = 13 − 15 TeV, the enhancement of multiplicities will generate new developments of EAS simulation, amended to take into account adequate guidelines of extrapolation; this will give the opportunity of a new interpretation of the cosmic ray results up to 10 20 eV.