IACT array performance and design study for multi-TeV gamma-ray astronomy

We outline here preliminary performance estimates of an array of modest‐sized (24 m2) Cherenkov imaging telescopes for multi‐TeV γ‐ray astronomy. We have considered an example sparse array of 9 cells of 5 telescopes arranged in a sparsely separated grid, for which the intercell spacing is 1.5 km, and each cell has a side telescope spacing of 500 m. Cosmic‐ray background rejection makes use of scaled Hillas‐based parameters, and additionaly, we incorporate direction reconstruction exploiting the time development of Cherenkov images, aiming to improve the imaging method at large core distances (typically >200 m). In the energy range we focus on at present, 10 to 100 TeV, this array provides energy flux sensitivities approaching 3×10−13 erg cm−2 s−1, representing a factor 5 to 10 improvement over H.E.S.S. A low altitude (0.2 km) site also provides an improved collection area vs. that obtained at a medium altitude (1.8 km). These preliminary results serve as useful guide in designing a telescope array for mul...