In the context of the development of a new detecting camera for the Cherenkov gamma-ray telescope TAIGA-IACT, the temperature dependences of the dark count rate and the efficiency of ultraviolet photon detection of two silicon avalanche photodetectors: OnSemi / SensL MicroFJ-60035 and Hamamatsu VUV4 S13371-6050CQ-02 at a wavelength of 277 nm were experimentally investigated. It is shown that the main characteristics of these detectors correspond to those declared by the manufacturers. Front-end readout electronics was developed and tested. Conclusions are drawn about the applicability of such detectors in the detecting cameras of Cherenkov gamma-ray telescopes.

Full-particle modeling of gamma-ray and proton induced extensive air showers (EASs) in the Earth's atmosphere as well as Monte Carlo modeling of photon transport in a small size Cherenkov telescope and signal registration with its camera based on the OnSemi MicroFJ SiPM detectors have been performed. Calculations have been carried out for primaries within the 0.3 - 30 TeV range and a telescope with a 10 m(2) mirror similar to the unit employed at the TAIGA observatory. It has been shown that even with strict selection criteria aimed at high quality EAS images, the threshold detection energy of the SiPM-based camera would not exceed 0.8 TeV - about twice as low as the current threshold of the TAIGA-IACT camera based on vacuum photomultipliers.

We have modeled propagation of source signal and noise for a future camera of TAIGA-IACT Cherenkov gamma-ray telescope, which will be based on silicon photomultipliers sensitive in the 240 -- 600 nm range. It has been shown that employment of such detectors instead of traditional vacuum photomultipliers will allow one to decrease the energy threshold by a factor of about 2.5: from ~ 1.5 TeV down to ~ 0.6 TeV. We have also shown that application of a standard ultraviolet filter ZWB3 will decrease the source signal by a factor of 3, while the noise signal from the night sky will be decreased by a factor of 6. In this way the duty cycle of the telescope can be extended (the telescope will be able to operate during moonlit nights and during twilight) and the energy threshold further decreased down to ~ 0.3 TeV. A narrow 260 -- 300 nm filter can be employed to improve gamma-hadron separation of primary cosmic particles in the ~ 25 -- 50 TeV band.

AbstractA position-sensitive module for detecting ionizing radiation based on semiconductor strip detectors and a multichannel spectrometric route has been developed and implemented. The dynamic range of the detected charge generated by an ionizing particle in the detector is 5–250 fC. The position-sensitive module is a structurally complete device with the functions of amplifying the spectrometric signal, digitizing, buffering, preprocessing, and transmitting data to a computer.

Поступило в Редакцию 1 июня 2017 г.В окончательной редакции 19 февраля 2018 г

AbstractAn IDS 2030 IonCCD coordinate-sensitive detector (Analytical/CMS Field Products) is interfaced with a small-sized mass spectrograph developed at the Ioffe Physical Technical Institute, Russian Academy of Sciences. The measurement data obtained with the mass spectrograph using an IonCCD detector and a Magnum-5901-37029PS channel secondary electron multiplier (Photonics USA Inc., United States) are compared. The results of measurements are discussed, and the prospects for using the IonCCD coupled with a microchannel plate are assessed.

Электронное и программное обеспечение автоматизированного портативного статического масс-спектрометра© Ю.В.Чичагов, 1 А