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The TAIGA (Tunka Advanced Instrument for cosmic ray physics and Gamma Astronomy) observatory is located in the Tunka valley (~50 km west from the southern shore of Lake Baikal) at an altitude of 675m a.s.l. The TAIGA observatory aims to address gamma-ray astronomy at energies from a few TeV to several PeV and CR physics from 100 TeV to several EeV. Its main feature is the complementary, hybrid approach to distinguish CR events from those of gamma rays. Currently TAIGA consists of ~80 wide-angle air Cherenkov detectors (HiSCORE stations), three ~4m diameter IACTs and several hundred surface and underground muon detectors, grouped in three jointly operating arrays. The exceptional feature of the TAIGA IACT array is it’s topology that allows one to aim for the optimal cost/performance by scanning the optimal inter-telescope distances from 300m up to 600m. The IACTs have alt-azimuth type mounts and 576-pixel imaging cameras in the foci, covering 9.6° aperture in the sky. The segmented reflectors of ~10m² area follow the Davis-Cotton design. The largest diameter of the hexagonal shape reflector is 4.3m and the focal length is 4.75m. The rigid telescope mount provides a maximum displacement of EAS image below 2mm (i.e. ≤ 0.024°) in the photodetector plane. The main parameters of IACTs are of a crucial importance for their efficient operation and is presented.

The pointing of Cherenkov telescopes is subject to imperfections which are, for example, related to the bending of the telescopes mechanical structure. These imperfections must be measured, modeled, and finally corrected to achieve an optimal telescope pointing precision. The measurement of pointing deviations is often performed while the telescope points to different stars and a CCD camera monitors the offsets of the star images to the center of the focal plane. Outliers in these measurements can propagate into the pointing model and lead to imprecise model predictions. CTbend is a simple and standalone open-source framework that uses a Bayesian analysis with an outlier resilient likelihood function to model the pointing of Cherenkov telescopes with parametric standard models like TPoint. The framework is described in the following.

In TAIGA (Tunka Advanced Instrument for cosmic ray physics and Gamma-ray Astronomy) detector we are commissioning the first Imaging Atmospheric Cherenkov Telescope (IACT). The telescope drive system comprises a motor controller and two stepper motors for axis control. For the pointing calibration of the telescope a CCD-camera is installed on the reflector dish of the telescope. The position of the CCD-camera allows us capturing both the Cherenkov camera and the observed source. In this report we describe the telescope positioning and the drive system software as well as the control of the CCD-camera data acquisition, archiving and processing system.