On the Potential of the Imaging Atmospheric Cherenkov Technique for Study of the Mass Composition of Primary Cosmic Radiation in the Energy Region above 30 TeV

摘要

We suggest a new approach to study the cosmis ray (CR) mass composition inthe energy region from 30 TeV/nucleus up to the "knee" region, i.e. up to a fewPeV/nucleus, using an array of imaging atmospheric Cherenkov telescopes (IACTs)of a special architecture. This array consists of telescopes with a relativelysmall mirror size (~10 square meters) separated from each other by largedistances (~500 meters) and equipped by multichannel cameras with a modestpixel size (0.3-0.5 degree) and a sufficiently large viewing angle (6-7degree). Compared to traditional IACT systems (like HEGRA, HESS or VERITAS) the IACTarray considered here could provide a very large detection area (several squarekilometers or more). At the same time, it allows an accurate measurement of theenergy of CR induced air showers (the energy resolution ranges within 25-35%)and an effective separation of air showers created by different nuclei.Particularly, it is possible to enrich air showers belonging to the nucleusgroup assigned for selection up to ~90% purity at a detection efficiency of15-20% of such showers.