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arXiv · 1903.12040

Potential for measuring the longitudinal and lateral profile of muons in TeV air showers with IACTs

Abstract

Muons are copiously produced within hadronic extensive air showers (EAS) occurring in the Earth's atmosphere, and are used by particle air shower detectors as a means of identifying the primary cosmic ray which initiated the EAS. Imaging Atmospheric Cherenkov Telescopes (IACTs), designed for the detection of gamma-ray initiated EAS for the purposes of Very High Energy (VHE) gamma-ray astronomy, are subject to a considerable background signal due to hadronic EAS. Although hadronic EAS are typically rejected for gamma-ray analysis purposes, single muons produced within such showers generate clearly identifiable signals in IACTs and muon images are routinely retained and used for calibration purposes. For IACT arrays operating with a stereoscopic trigger, when a muon triggers one telescope, other telescopes in IACT arrays usually detect the associated hadronic EAS. We demonstrate for the first time the potential of IACT arrays for competitive measurements of the muon content of air showers, their lateral distribution and longitudinal profile of production slant heights in the TeV energy range. Such information can provide useful input to hadronic interaction models.

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A. M. W. Mitchell, H. P. Dembinski, R. D. Parsons. 2019-03-28. Potential for measuring the longitudinal and lateral profile of muons in TeV air showers with IACTs. https://doi.org/10.1016/j.astropartphys.2019.03.005

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