Effects of charm particles in Extensive Air Showers

Abstract

Charmed particles are rare in Extensive Air Showers (EASs), but their effects can be radical in the EASs development. If such particles carry a large fraction of primary energy, they can to reach large atmospheric depths, depositing their energy in deeper layers of the atmosphere, changing the EAS observables ($X_{max}$, $RMS$ and $N_{max}$) and the shape of the longitudinal profile of the energy deposited in the atmosphere. Very energetic charmed hadrons may be produced in the upper atmosphere when a primary cosmic ray or a leading hadron in the EASs collides with the air. Since the inelasticity in these collisions is much smaller than in proton and pion collisions, we will have rare events in which a heavy hadron particle transport a significant amount of energy deep into the atmosphere. A heavy particle's energy deposition relatively near the ground produces muons and other particles that could change significantly the EASs longitudinal profile seen in the Fluorescence Detector and/or the temporal distribution and signal observed in the ground detectors. In this contribution we consider a modified version of the EAS simulator, CORSIKA, which takes into account the production of charmed particles in the first interaction of the primary cosmic ray. The heavy charmed particles are produced via Intrinsic Quark Model (IQM) model. We present results for the EAS longitudinal profile and lateral distribution of particles, and analyze the implications in the EAS reconstruction parameters.