2017/08/03 by S. Thoudam, Y. Becherini, Thoudam, Satyendra +3
Physics and Astronomy · #Astrophysics and Cosmic Phenomena #Dark Matter and Cosmic Phenomena #FOS: Physical sciences #Instrumentation and Detectors (physics.ins-det) #Instrumentation and Methods for Astrophysics (astro-ph.IM) #Particle Detector Development and Performance
paper · pdf · doi:10.48550/arxiv.1708.01059
openalex publication_date 2017/08/03 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
ALTO is a wide field-of-view air shower detector array for very-high-energy\n(VHE) gamma-ray astronomy, proposed to be installed in the Southern Hemisphere\nat an altitude of about 5.1 km above sea level. The array will use water\nCherenkov detectors, as in the HAWC observatory, but combined with scintillator\ndetectors, to detect air showers induced by VHE gamma rays in the atmosphere.\nIt is being designed to attain a lower energy threshold, better energy and\nangular resolution, and improved sensitivity. The array will consist of about\n1250 small-sized (3.6 m diameter) detector units distributed over a circular\narea of about 160 m in diameter. Each detector unit will consist of a water\nCherenkov detector and a liquid scintillation detector underneath which will\npreferentially identify muons, facilitating the background (cosmic ray)\nrejection, thereby improving the sensitivity. The background rejection will be\nfurther enhanced by the close-packed arrangement and the small size of the\ndetectors which will allow a fine sampling of air-shower footprints at the\nground. In this contribution, we present the Monte-Carlo simulation of the\nexperiment performed using CORSIKA and GEANT4 simulation packages. The expected\nperformance of the array in terms of reconstruction accuracies of the shower\ncore and arrival direction, as well as preliminary estimate of the trigger\nenergy threshold after preliminary selection cuts for a point-like gamma-ray\nsource are presented.\n