Ground-based detectors in very-high-energy gamma-ray astronomy

TL;DR

This paper reviews the development, current state, and future prospects of ground-based very-high-energy gamma-ray astronomy, highlighting technological advancements and the increasing sensitivity of detection instruments that have expanded our understanding of the non-thermal Universe.

Contribution

It provides a comprehensive overview of detection techniques, historical progress, and future directions in ground-based gamma-ray astronomy, emphasizing recent technological innovations.

Findings

Detection of numerous astrophysical gamma-ray sources

Development of more sensitive ground-based instruments

Expansion of the non-thermal Universe observations

Abstract

Following the discovery of the cosmic rays by Victor Hess in 1912, more than 70 years and numerous technological developments were needed before an unambiguous detection of the first very-high-energy gamma-ray source in 1989 was made. Since this discovery the field on very-high-energy gamma-ray astronomy experienced a true revolution: A second, then a third generation of instruments were built, observing the atmospheric cascades from the ground, either through the atmospheric Cherenkov light they comprise, or via the direct detection of the charged particles they carry. Present arrays, 100 times more sensitive than the pioneering experiments, have detected a large number of astrophysical sources of various types, thus opening a new window on the non-thermal Universe. New, even more sensitive instruments are currently being built; these will allow us to explore further this fascinating domain. In this article we describe the detection techniques, the history of the field and the prospects for the future of ground-based very-high-energy gamma-ray astronomy.