IACT

The Major Atmospheric Cerenkov Experiment Telescope (MACE) is under construction in Hanle, Ladakh, India and is set to be the highest and second-largest IACT.

The Cherenkov Telescope Array (CTA) is a multinational project to build next-generation IACTs and is scheduled to begin data collection in 2022.

In the case of the IACT, the Earth's atmosphere is used as the detection medium, implying a collection area of many hundreds of square meters.

The IACT works by imaging the very short flash of Cherenkov radiation generated by the cascade of relativistic charged particles produced when a very-high-energy gamma ray strikes the atmosphere.

A cascade of charged particles ensues which, due to its extreme energy, produces a flash of Cherenkov radiation lasting between 5 and 20 ns.

The primary advantage of this mode of operation is that the energy threshold (the peak sensitivity) of the telescope can be lowered as local muons produced by cosmic ray induced showers can be eliminated.

MAGIC , a Cherenkov telescope in operation on the Canary island of La Palma . On foggy nights, the lasers that are used to focus the mirrors can be seen.