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Optical EVPA rotations in blazars: testing a stochastic variability model with RoboPol data

Kiehlmann, S. and Blinov, D. and Pearson, T. J. and Liodakis, I. (2017) Optical EVPA rotations in blazars: testing a stochastic variability model with RoboPol data. Monthly Notices of the Royal Astronomical Society, 472 (3). pp. 3589-3604. ISSN 0035-8711.

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We identify rotations of the polarization angle in a sample of blazars observed for three seasons with the RoboPol instrument. A simplistic stochastic variability model is tested against this sample of rotation events. The model is capable of producing samples of rotations with parameters similar to the observed ones, but fails to reproduce the polarization fraction at the same time. Even though we can neither accept nor conclusively reject the model, we point out various aspects of the observations that are fully consistent with a random walk process.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Kiehlmann, S.0000-0001-6314-9177
Pearson, T. J.0000-0001-5213-6231
Liodakis, I.0000-0001-9200-4006
Additional Information:© 2017 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. Accepted 2017 August 17. Received 2017 August 16; in original form 2017 June 8. Published: 23 August 2017. The RoboPol project is a collaboration between the University of Crete/FORTH in Greece, Caltech in the USA, MPIfR in Germany, IUCAA in India and Toruń Centre for Astronomy in Poland. This research was supported in part by NASA grants NNX11A043G and NNX16AR41G and NSF grant AST-1109911. SK is supported through NASA grant NNX13AQ89G. This research was partly funded by the Academy of Finland project 284495. SK particularly thanks T. Savolainen for comments on this manuscript and for the support of this research. The authors furthermore thank E. Angelakis, T. Hovatta, V. Pavlidou and K. Tassis from the RoboPol collaboration for comments and intense discussions during the collaboration meetings. This research was done with PYTHON packages NUMPY 1.11.3—, SCIPY 0.18.1—, STATSMODELS 0.6.1—, PYTABLES 3.3.0— and MATPLOTLIB 2.0.0—.
Group:Owens Valley Radio Observatory (OVRO)
Funding AgencyGrant Number
Academy of Finland284495
Subject Keywords:polarization – galaxies: active – galaxies: jets – galaxies: nuclei
Issue or Number:3
Record Number:CaltechAUTHORS:20171102-160804515
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Official Citation:S. Kiehlmann, D. Blinov, T. J. Pearson, I. Liodakis; Optical EVPA rotations in blazars: testing a stochastic variability model with RoboPol data, Monthly Notices of the Royal Astronomical Society, Volume 472, Issue 3, 11 December 2017, Pages 3589–3604,
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:82919
Deposited By: Tony Diaz
Deposited On:03 Nov 2017 02:17
Last Modified:20 May 2020 19:29

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