The TeV Sky and Multiwavelength Astrophysics

TeV \(\upgamma \)-ray astronomy is outside the possibility of space-based experiments and can be at present studied only through ground-based experiments. However, because of the high background induced by CR showers, the large collection areas alone cannot provide adequate sensitivities for effective studies of cosmic \(\upgamma \)-rays. The capability to suppress the events induced by charged CRs was made possible with the advent of the Imaging Air Cherenkov Technique (IACT), Sect. 9.1 and with some dedicated air shower particle arrays, Sect. 9.2.