Modeling for Pointing of Imaging Atmospheric Cherenkov Telescopes in Taiga Experiment

TAIGA-IACT telescopes are Imaging Atmospheric Cherenkov telescopes that are part of the hybrid experimental complex TAIGA, located 50 km from Lake Baikal in the Tunka Valley, Republic of Buryatia, Russia. The telescope operation requires accurate determination of the telescope direction and the position of a source on the camera plane. The telescope positioning system consists of stepper motors, shaft encoders, and a CCD camera mounted on the telescope dish. The position of the telescope is determined using shaft encoders with a pointing model, as well as using CCD camera images by astrometry of the sky region. The positions of sources on the telescope camera are calculated using the camera model and the estimated telescope direction. The telescope focal plane rotation angle is calculated by knowing the telescope pointing model parameters. This paper presents the developed models and methods used for the TAIGA-IACT telescope pointing.

Keywords

telescope pointing model; IACT; TAIGA experiment.

References

1. Budnev, N. TAIGA - an advanced hybrid detector complex for astroparticle physics and high energy gamma-ray astronomy in the Tunka valley / N. Budnev, I. Astapov, P. Bezyazeekov, E. Bonvech, V. Boreyko et al // Journal of instrumentation. - 2020. - P. C09031.
2. Kuzmichev, L. Experimental Complex TAIGA / L. Kuzmichev, I. Astapov, P. Bezyazykov, M. Blank, A. Borodin // Physics of Atomic Nuclei. - 2020. - V. 83, № 9. - P. 1375-1382.
3. Gress, O. The Wide-Aperture Gamma-Ray Telescope TAIGA-HiSCORE in the Tunka Valley: Design, Composition and Commissioning / O. Gress, I. Astapov, N. Budnev, P. Bezyazeekov, A. Bogdanov // Nuclear Instruments and Methods in Physics Research. - 2017. - V. 845. - P. 367-372.
4. Sveshnikova, L.G. Detecting Gamma Rays with Energies Greater than 3–4 ТeV from the Crab Nebula and Blazar Markarian 421 by Imaging Atmospheric Cherenkov Telescopes in the TAIGA Experiment / L.G. Sveshnikova, M. Blank, A. Bulan, P. Volchugov, N.N. Kalmykov // Bulletin of the Russian Academy of Sciences: Physics. - 2021. - V. 85, № 4. - P. 398-401.
5. Zhurov, D. First Results of the Tracking System Calibration of the TAIGA-IACT Telescope / D. Zhurov, O. Gress, D. Sidorov, I. Astapov, P. Bezyazeekov // Journal of Physics. - 2019. - V. 1181, № 1. - Article ID: 012045.
6. Forsyth, D.A. Computer Vision: a Modern Approach / D.A. Forsyth, J. Ponce. - Boston: Pearson Education, 2003.
7. Grinyuk, A. Monte Carlo Simulation of the TAIGA Hybrid Gamma-Ray Experiment / A. Grinyuk, E. Postnikov, L. Sveshnikova // Physics of Atomic Nuclei. - 2020. - V. 83, № 2. - P. 262-267.
8. Condon, J.J. GBT Pointing Equations / J.J. Condon // GBT Memos and Reports. - 1992. - V. 75. - P. 1-15.
9. Mangum, J.G. Evaluation of the ALMA Prototype Antennas / J.G. Mangum, J.W.M. Baars, A. Greve, R. Lucas, R.C. Snel, P.T. Wallace, M. Holdaway // IOP Publishing. - 2006. - P. 1257-1301.
10. Lew, B. Improving Pointing of Torun 32-m Radio Telescope: Effects of Rail Surface Irregularities / B. Lew // Experimental Astronomy. - 2018. - V. 45. - P. 81-105.
11. Wallace, P.T. Rigorous Algorithm for Telescope Pointing / P.T. Wallace // Advanced Telescope and Instrumentation Control Software. - 2002. - P. 125-136.
12. Zhurov, D.P. Glare Separation and Parametrization of Images of Stars on the Calibration Screen for Imaging Atmospheric Cherenkov Telescopes TAIGA-IACT / D.P. Zhurov, D.N. Sidorov // South Ural Youth School of Mathematical Modeling - Chelyabinsk: SUSU Publishing Center, 2021.