The application potential of silicon photomultipliers for a camera of a small-size Cherenkov gamma-ray telescope for reducing the detection threshold

Source and noise signals in a new camera of the TAIGA-IACT Cherenkov $\gamma$-ray telescope based on silicon photomultipliers (SiPM) have been simulated. It is shown that application of modern silicon photomultipliers as detecting elements of TAIGA-IACT (instead of the currently used conventional vacuum photomultipliers) will make it possible to reduce the threshold detection energy of cosmic $\gamma$ quanta by a factor of about 2.5 (from $\simeq$ 1.5 to $\simeq$ 0.6 TeV). It is also shown that employment of a standard ZWB3 UV filter mask in the TAIGA-IACT camera would reduce the average signal level by a factor of about 3 and the noise (background) level from the night sky by a factor of about 6, which would allow one to extend the duty cycle of the telescope (in particular, to carry out observations during moonlit nights and twilights) and to additionally reduce the threshold detection energy down to $\simeq$ 0.3 TeV. The application of a narrower UV filter of 260–300 nm bandwidth can increase the efficiency of determining the primary particle type ($\gamma$-hadron separation) in the energy range from $\sim$25 up to $\sim$50 TeV.