Reconstruction of the muon production depth with ground array data based on the TTC (Time-Track Complementarity) approach

Abstract

Abstract. The muon longitudinal profile along the shower axis depends on the nature of the primary particle and primary hadronic interaction with air nuclei. The measurement of muonic component inside showers generated by Very High Energy Cosmic Rays provides a very powerful tool for sensing high energy interactions between cosmic ray particles and air molecules. Fundamental parameters such as the interaction cross section, inelasticity, hadron production and multiplicity can be measured by comparing the development of shower electromagnetic component with that of muonic component. Since 1992 a method has been developed to combine the muon arrival direction in a ground based array for cosmic ray detection with their arrival delay with respect to the shower core. This combination permits to select high energy muons weakly scattered in the atmosphere and to reconstruct their height of production with good accuracy. In this paper we discuss the possibility to realize a "dual" apparatus able to detect both electromagnetic and muonic component at primary energies greater than 10 17 eV.

Some closing marks made at the CERN symposium on future directions in UHECR physics

“…RPCs are also being proposed as a suitable tool. An ambitious scheme to use these devices was described [11] which complements another RPC plan presented earlier this year [12]. It is clear that several lines of R&D should be explored before deciding which is the most promising.…”