Performance of the Cherenkov Telescope Array in the presence of clouds
(2022) 37th International Cosmic Ray Conference In Proceedings of Science 395.- Abstract
- The Cherenkov Telescope Array (CTA) is the future ground-based observatory for gamma-ray astronomy at very high energies. The atmosphere is an integral part of every Cherenkov telescope. Different atmospheric conditions, such as clouds, can reduce the fraction of Cherenkov photons produced in air showers that reach ground-based telescopes, which may affect the performance. Decreased sensitivity of the telescopes may lead to misconstructed energies and spectra. This study presents the impact of various atmospheric conditions on CTA performance. The atmospheric transmission in a cloudy atmosphere in the wavelength range from 203 nm to 1000 nm was simulated for different cloud bases and different optical depths using the MODerate resolution... (More)
- The Cherenkov Telescope Array (CTA) is the future ground-based observatory for gamma-ray astronomy at very high energies. The atmosphere is an integral part of every Cherenkov telescope. Different atmospheric conditions, such as clouds, can reduce the fraction of Cherenkov photons produced in air showers that reach ground-based telescopes, which may affect the performance. Decreased sensitivity of the telescopes may lead to misconstructed energies and spectra. This study presents the impact of various atmospheric conditions on CTA performance. The atmospheric transmission in a cloudy atmosphere in the wavelength range from 203 nm to 1000 nm was simulated for different cloud bases and different optical depths using the MODerate resolution atmospheric TRANsmission (MODTRAN) code. MODTRAN output files were used as inputs for generic Monte Carlo simulations. The analysis was performed using the MAGIC Analysis and Reconstruction Software (MARS) adapted for CTA. As expected, the effects of clouds are most evident at low energies, near the energy threshold. Even in the presence of dense clouds, high-energy gamma rays may still trigger the telescopes if the first interaction occurs lower in the atmosphere, below the cloud base. A method to analyze very high-energy data obtained in the presence of clouds is presented. The systematic uncertainties of the method are evaluated. These studies help to gain more precise knowledge about the CTA response to cloudy conditions and give insights on how to proceed with data obtained in such conditions. This may prove crucial for alert-based observations and time-critical studies of transient phenomena. © Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0) (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/b5d8982d-56df-4cf3-bf90-de35263e0d5e
- author
- Pecimotika, M.
; Adamczyk, Katarzyna
; Prester, Dijana Dominis
; Gueta, Orel
; Hrupec, Dario
; Maier, Gernot
; Mićanović, Saša
; Pavletić, Lovro
; Sitarek, Julian
; Sobczyńska, Dorota
; Szanecki, Michał
; Carlile, C.
LU
; Dravins, D.
LU
and Zmija, A.
(Less) - author collaboration
- organization
- publishing date
- 2022
- type
- Chapter in Book/Report/Conference proceeding
- publication status
- published
- subject
- keywords
- Cosmic rays, Cosmology, Gamma rays, Intelligent systems, Light transmission, Telescopes, Atmospheric conditions, Atmospheric transmissions, Cherenkov telescope arrays, Cloud base, Gamma-ray astronomy, Ground based observatories, Integral part, Moderate resolution, Performance, Very high energies, Monte Carlo methods
- host publication
- 37th International Cosmic Ray Conference (ICRC2021) - GAI - Gamma Ray Indirect
- series title
- Proceedings of Science
- volume
- 395
- article number
- 763
- conference name
- 37th International Cosmic Ray Conference
- conference location
- Berlin, Germany
- conference dates
- 2021-07-12 - 2021-07-23
- external identifiers
-
- scopus:85144605866
- ISSN
- 1824-8039
- DOI
- 10.22323/1.395.0773
- language
- English
- LU publication?
- yes
- id
- b5d8982d-56df-4cf3-bf90-de35263e0d5e
- date added to LUP
- 2023-01-16 14:13:27
- date last changed
- 2024-04-03 18:25:43
@inproceedings{b5d8982d-56df-4cf3-bf90-de35263e0d5e,
abstract = {{The Cherenkov Telescope Array (CTA) is the future ground-based observatory for gamma-ray astronomy at very high energies. The atmosphere is an integral part of every Cherenkov telescope. Different atmospheric conditions, such as clouds, can reduce the fraction of Cherenkov photons produced in air showers that reach ground-based telescopes, which may affect the performance. Decreased sensitivity of the telescopes may lead to misconstructed energies and spectra. This study presents the impact of various atmospheric conditions on CTA performance. The atmospheric transmission in a cloudy atmosphere in the wavelength range from 203 nm to 1000 nm was simulated for different cloud bases and different optical depths using the MODerate resolution atmospheric TRANsmission (MODTRAN) code. MODTRAN output files were used as inputs for generic Monte Carlo simulations. The analysis was performed using the MAGIC Analysis and Reconstruction Software (MARS) adapted for CTA. As expected, the effects of clouds are most evident at low energies, near the energy threshold. Even in the presence of dense clouds, high-energy gamma rays may still trigger the telescopes if the first interaction occurs lower in the atmosphere, below the cloud base. A method to analyze very high-energy data obtained in the presence of clouds is presented. The systematic uncertainties of the method are evaluated. These studies help to gain more precise knowledge about the CTA response to cloudy conditions and give insights on how to proceed with data obtained in such conditions. This may prove crucial for alert-based observations and time-critical studies of transient phenomena. © Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0)}},
author = {{Pecimotika, M. and Adamczyk, Katarzyna and Prester, Dijana Dominis and Gueta, Orel and Hrupec, Dario and Maier, Gernot and Mićanović, Saša and Pavletić, Lovro and Sitarek, Julian and Sobczyńska, Dorota and Szanecki, Michał and Carlile, C. and Dravins, D. and Zmija, A.}},
booktitle = {{37th International Cosmic Ray Conference (ICRC2021) - GAI - Gamma Ray Indirect}},
issn = {{1824-8039}},
keywords = {{Cosmic rays; Cosmology; Gamma rays; Intelligent systems; Light transmission; Telescopes; Atmospheric conditions; Atmospheric transmissions; Cherenkov telescope arrays; Cloud base; Gamma-ray astronomy; Ground based observatories; Integral part; Moderate resolution; Performance; Very high energies; Monte Carlo methods}},
language = {{eng}},
series = {{Proceedings of Science}},
title = {{Performance of the Cherenkov Telescope Array in the presence of clouds}},
url = {{http://dx.doi.org/10.22323/1.395.0773}},
doi = {{10.22323/1.395.0773}},
volume = {{395}},
year = {{2022}},
}