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Flux States of Active Galactic Nuclei

Institute for Theoretical Physics and Astrophysics, University of Würzburg, 97074 Würzburg, Germany
Institute for Particle Physics and Astrophysics, ETH Zurich, 8093 Zurich, Switzerland
Experimental Physics 5, TU Dortmund, 44221 Dortmund, Germany
ISDC Data Centre for Astrophysics, University of Geneva, CH-1290 Versoix, Switzerland
Author to whom correspondence should be addressed.
also at: Department of Physics, RWTH Aachen University, 52074 Aachen, Germany.
Galaxies 2019, 7(2), 57;
Received: 21 February 2019 / Revised: 24 April 2019 / Accepted: 30 April 2019 / Published: 21 May 2019
(This article belongs to the Special Issue Monitoring the Non-Thermal Universe)
Blazars are known to show variability on time scales from minutes to years covering a wide range of flux states. Studying the flux distribution of a source allows for various insights. The shape of the flux distribution can provide information on the nature of the underlying variability processes. The level of a possible quiescent state can be derived from the main part of the distribution that can be described by a Gaussian distribution. Dividing the flux states into quiescent and active, the duty cycle of a source can be calculated. Finally, this allows alerting the multi-wavelength and multi-messenger community in case a source is in an active state. To get consistent and conclusive results from flux distributions, unbiased long-term observations are crucial. Only like this is a complete picture of the variability and flux states, e.g., an all-time quiescent state, possible. In seven years of monitoring of bright TeV blazars, the first G-APD Cherenkov telescope (FACT) has collected a total of more than 11,700 hours of physics data with 1500 hours to 3000 hours per source for Mrk 421, Mrk 501, 1ES 1959+650, and 1ES 2344+51. View Full-Text
Keywords: active galactic nuclei; blazars; monitoring; TeV energies; FACT; flux states; flux distributions; duty cycle active galactic nuclei; blazars; monitoring; TeV energies; FACT; flux states; flux distributions; duty cycle
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MDPI and ACS Style

Dorner, D.; Arbet-Engels, A.; Baack, D.; Balbo, M.; Biland, A.; Blank, M.; Bretz, T.; Bruegge, K.; Bulinski, M.; Buss, J.; Doerr, M.; Elsaesser, D.; Hildebrand, D.; Linhoff, L.; Mannheim, K.; Mueller, S.A.; Neise, D.; Neronov, A.; Noethe, M.; Paravac, A.; Rhode, W.; Schleicher, B.; Schulz, F.; Sedlaczek, K.; Shukla, A.; Sliusar, V.; von Willert, E.; Walter, R.; FACT Collaboration. Flux States of Active Galactic Nuclei. Galaxies 2019, 7, 57.

AMA Style

Dorner D, Arbet-Engels A, Baack D, Balbo M, Biland A, Blank M, Bretz T, Bruegge K, Bulinski M, Buss J, Doerr M, Elsaesser D, Hildebrand D, Linhoff L, Mannheim K, Mueller SA, Neise D, Neronov A, Noethe M, Paravac A, Rhode W, Schleicher B, Schulz F, Sedlaczek K, Shukla A, Sliusar V, von Willert E, Walter R, FACT Collaboration. Flux States of Active Galactic Nuclei. Galaxies. 2019; 7(2):57.

Chicago/Turabian Style

Dorner, Daniela, Axel Arbet-Engels, Dominik Baack, Matteo Balbo, Adrian Biland, Michael Blank, Thomas Bretz, Kai Bruegge, Michael Bulinski, Jens Buss, Manuel Doerr, Dominik Elsaesser, Dorothee Hildebrand, Lena Linhoff, Karl Mannheim, Sebastian A. Mueller, Dominik Neise, Andrii Neronov, Maximilian Noethe, Aleksander Paravac, Wolfgang Rhode, Bernd Schleicher, Florian Schulz, Kevin Sedlaczek, Amit Shukla, Vitalii Sliusar, Elan von Willert, Roland Walter, and FACT Collaboration. 2019. "Flux States of Active Galactic Nuclei" Galaxies 7, no. 2: 57.

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