Abstract
The Imaging Atmospheric Cherenkov technique allows us to detect very high-energy gamma rays from few tens of GeV to hundreds of TeV using ground-based instrumentation. At these energies, a gamma ray generates a shower of secondary particles when it enters the Earth’s atmosphere. These particles emit the Cherenkov light in the visible and near-UV ranges. The Cherenkov light produced by the shower reaches the ground as a short pulse of a few nanosecond duration over a large circle of around 100 m radius (a light pool). This pulse of light can be imaged with telescopes provided with fast photodetectors and electronics. Combining the images of several telescopes distributed over this light pool allows us to estimate the gamma-ray energy and incident direction and to reject gamma rays from the strong background of charged cosmic rays. The collection area of an array of a few telescopes is of the order of the area of the light pool, i.e., >105 m2. Such an array reaches a sensitivity of a few millicrabs at 100 GeV energies in 50 h of observations, an angular resolution of ∼5 arcmin, and a spectral resolution of ∼10%. This chapter describes the technical implementation of Imaging Atmospheric Cherenkov telescopes and also describes how the data are analyzed to reconstruct the physical parameters of the primary gamma rays.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Similar content being viewed by others
References
Handbook of X-Ray and Gamma-Ray astrophysics, The Major Gamma-ray Imaging Cherenkov Telescopes (MAGIC), The Very Energetic Radiation Imaging Telescope Array System (VERITAS) and The High Energy Stereoscopic System (H.E.S.S.), Section 6 (Springer)
Handbook of X-Ray and Gamma-Ray astrophysics, The Cherenkov Telescope array (CTA): a worldwide endeavor for the next level of ground-based gamma-ray astronomy, Section 6 (Springer)
Handbook of X-Ray and Gamma-Ray Astrophysics, Future developments in ground-based gamma-ray astronomy, Section 6 (Springer)
Handbook of X-Ray and Gamma-Ray Astrophysics, Sections 7–15 (Springer)
Handbook of X-Ray and Gamma-Ray Astrophysics, Section 16–19 (Springer)
J. Albert et al., (MAGIC collaboration), FADC signal reconstruction for the MAGIC telescope. NIM A 594, 407–419 (2008a)
J. Albert et al., (MAGIC collaboration), Implementation of the random forest method for the imaging atmospheric Cherenkov telescope MAGIC. NIM A 588, 424–432 (2008b)
E. Aliu et al., (MAGIC collaboration), Improving the performance of the single-dish Cherenkov telescope MAGIC through the use of signal timing. Astropart. Phys. 30, 293 (2009)
A. Barrau et al., The CAT imaging telescope for very-high-energy gamma-ray astronomy. NIM A 416, 278–292 (1998)
P.A. Cherenkov, Visible emission of clean liquids by action of γ radiation. Dokl. Akad. Nauk SSSR 2, 451 (1934)
J. Cortina, A. Moralejo, R. Lopez-Coto, MACHETE: a transit imaging atmospheric Cherenkov telescope to survey half of the very high energy gamma-ray sky. Astrop. Phys. 72, 46–54 (2016).
A. Couder, Sur un type nouveau de télescope photographique. Compt. Rend. Acad. Sci. Paris 45, 1276 (1926)
A. Daum et al., (The HEGRA Collaboration), First results on the performance of the HEGRA IACT array. Astropart. Phys. 8, 1–11 (1997)
J.M. Davies, E.S. Cotton, Design of the quartermaster solar furnace. J. Sol. Energy Sci. Eng. 1, 16 (1957)
G. Emery et al., Reconstruction of extensive air shower images of the first Large Size Telescope prototype of CTA using a novel likelihood technique, in PoS (ICRC2021) (2021), p. 716
D. Heck et al., CORSIKA: a Monte Carlo code to simulate extensive air showers, Technical Report, FZKA-6019, Forschungszentrum Karlsruhe (1998)
W. Heitler, The Quantum Theory of Radiation (1954) (Oxford University Press), ISBN-10 0198512120
A. Hillas, Cherenkov light images of EAS produced by primary gamma, in Proceedings of 19th ICRC (La Jolla), vol. 3 (1985), p. 445
M. Lemoine-Goumard et al., 3D-reconstruction of gamma-ray showers with a stereoscopic system, in Proceedings of toward Network of Atmospheric Cherenkov Detectors VII (2005), pp. 173–182
MAGIC collaboration, Measurement of the Crab Nebula spectrum over three decades in energy with the MAGIC telescopes. J. High Energy Astrophys. 5–6, 30–38 (2015)
MAGIC collaboration, The major upgrade of the MAGIC telescopes, part II: A performance study using observations of the Crab Nebula. Astropart. Phys. 72, 76 (2016)
R. Mirzoyan, M.I. Andersen, A 15 deg wide field of view imaging air Cherenkov telescope. Astrop. Phys. 31, 1–5 (2009)
S.A. Mueller, Cherenkov-Plenoscope (2019). arXiv:1904.13368
M. de Naurois et al., Application of an analysis method based on a semi-analytical shower model to the first H.E.S.S. telescope, in Proceedings of 28th ICRC (2003), p. 2907
D. Nieto et al., Exploring deep learning as an event classification method for the Cherenkov Telescope Array, in Proceedings of 35th ICRC, (2017)
Preliminary Sensitivity Curves for H.E.S.S.-I (stereo reconstruction), based on/adapted from Holler et al., in Proceedings of the 34th ICRC (2015)
S. Preuß, G. Hermann, W. Hofmann, A. Kohnle, Study of the photon flux from the night sky at La Palma and Namibia, in the wavelength region relevant for imaging atmospheric Cherenkov telescopes. NIM A 481, 229–240 (2002)
A. Schliesser, R. Mirzoyan, Wide-field prime-focus imaging atmospheric Cherenkov telescopes: a systematic study. Astrop. Phys. 24, 382 (2005)
VERITAS: public specifications webpage. https://veritas.sao.arizona.edu/about-veritas/veritas-specifications
C.T. Weekes et al., (Whipple collaboration), Observation of TeV gamma rays from the crab nebula using the atmospheric Cerenkov imaging technique. Astrophys. J. 342, 379–395 (1989)
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2024 Springer Nature Singapore Pte Ltd.
About this entry
Cite this entry
Cortina, J., Delgado, C. (2024). Detecting Gamma Rays with High Resolution and Moderate Field of View: The Air Cherenkov Technique. In: Bambi, C., Santangelo, A. (eds) Handbook of X-ray and Gamma-ray Astrophysics. Springer, Singapore. https://doi.org/10.1007/978-981-19-6960-7_63
Download citation
DOI: https://doi.org/10.1007/978-981-19-6960-7_63
Published:
Publisher Name: Springer, Singapore
Print ISBN: 978-981-19-6959-1
Online ISBN: 978-981-19-6960-7
eBook Packages: Physics and AstronomyReference Module Physical and Materials ScienceReference Module Chemistry, Materials and Physics