https://doi.org/10.1140/epjs/s11734-021-00396-3
Review
Ground-based gamma-ray astronomy: history and development of techniques
1
Department of Astrophysics and Cosmology, S. N. Bose National Centre for Basic Sciences, Kolkata, India
2
Department of High Energy Physics, Tata Institute of Fundamental Research, Mumbai, India
3
High Energy Nuclear and Particle Physics Division, Saha Institute of Nuclear Physics, Kolkata, India
4
Department of Astrophysics, Faculty of Physics and Applied Informatics, University of Lodz, Lodz, Poland
Received:
1
November
2021
Accepted:
13
December
2021
Published online:
30
December
2021
Very high energy (VHE) 
-rays constitute one of the main pillars of high energy astrophysics. Gamma-rays are produced under extreme relativistic conditions in the Universe. VHE -rays can be detected indirectly on the ground. Detection of these energetic photons poses several technological challenges. First, even though -rays are highly penetrative, the Earth’s atmosphere is opaque to them. Second, these -rays are to be detected against the overwhelming background of cosmic rays. When a VHE -ray arrives at the top of the atmosphere, it produces charged secondaries. These charged particles produce Cherenkov flashes in optical band. Even though first attempts to detect these Cherenkov flashes were made almost 70 years ago, it took several decades of relentless efforts to streamline the technique. Ground-based VHE -ray astronomy has now established itself as one of the crucial branches of conventional high energy astronomy to study the relativistic Universe. In this article, we look back and present a historical perspective followed by a discussion on the current status and finally what lays ahead.
© The Author(s), under exclusive licence to EDP Sciences, Springer-Verlag GmbH Germany, part of Springer Nature 2021
