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Milliarcsecond Core Size Dependence of the Radio Variability of Blazars

Published online by Cambridge University Press:  11 September 2023

Po-Chih Hsu
Affiliation:
Institute of Astronomy and Astrophysics, Academia Sinica, Taipei 10617, Taiwan (R.O.C.) Graduate Institute of Astronomy, National Central University, Taoyuan 32001, Taiwan (R.O.C.)
Jun Yi Koay
Affiliation:
Institute of Astronomy and Astrophysics, Academia Sinica, Taipei 10617, Taiwan (R.O.C.)
Satoki Matsushita
Affiliation:
Institute of Astronomy and Astrophysics, Academia Sinica, Taipei 10617, Taiwan (R.O.C.)
Chorng-Yuan Hwang
Affiliation:
Graduate Institute of Astronomy, National Central University, Taoyuan 32001, Taiwan (R.O.C.)
Talvikki Hovatta
Affiliation:
Finnish Centre for Astronomy with ESO (FINCA), University of Turku, FI-20014 Turku, Finland Aalto University Metsähovi Radio Observatory, Metsähovintie 114, FI-02540 Kylmälä, Finland
Sebastian Kiehlmann
Affiliation:
Owens Valley Radio Observatory, California Institute of Technology, Pasadena, CA 91125, USA Institute of Astrophysics, Foundation for Research and Technology-Hellas, GR-71110 Heraklion, Greece Department of Physics, University of Crete, GR-70013 Heraklion, Greece
Walter Max-Moerbeck
Affiliation:
Departamento de Astronomía, Universidad de Chile, Camino El Observatorio 1515, Las Condes, Santiago, Chile
Tim Pearson
Affiliation:
Owens Valley Radio Observatory, California Institute of Technology, Pasadena, CA 91125, USA
Anthony Readhead
Affiliation:
Owens Valley Radio Observatory, California Institute of Technology, Pasadena, CA 91125, USA
Rodrigo Reeves
Affiliation:
Departamento de Astronomía, Universidad de Conceptión, Concepción, Chile
Harish Vedantham
Affiliation:
Cahill Center for Astronomy and Astrophysics, California Institute of Technology, 1200 E. California Blvd., Pasadena, CA 91125, USA Netherlands Institute for Radio Astronomy (ASTRON), Oude Hogeveensedijk 4, NL-7991 PD Dwingeloo, the Netherlands

Abstract

Studying blazar radio variability on timescales ranging from months to years provides information on the sub-parsec-scale structures of the jets, and the physics of the central active galactic nuclei. In this study, we focus on the radio variability of 1158 blazars observed at 15 GHz through the Owens Valley Radio Observatory Blazar Monitoring Program, where these sources have been observed about twice a week for over a decade. We investigate the dependence of the variability amplitudes and timescales, derived using a simple model fit to the structure function, on the milliarcsecond radio core sizes measured by Very Long Baseline Interferometry. The most compact sources exhibit larger variability amplitudes and shorter variability timescales than the more extended sources; this could be explained by light travel-time effects.

Type
Contributed Paper
Copyright
© The Author(s), 2023. Published by Cambridge University Press on behalf of International Astronomical Union

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References

Alexander, K. D. et al., 2020, Space Sci. Rev., 216, 81 CrossRefGoogle Scholar
Ghisellini, G. and Tavecchio, F., 2009, MNRAS, 397, 985 CrossRefGoogle Scholar
Healey, S. E. et al., 2008, ApJS, 175, 97 CrossRefGoogle Scholar
Hovatta, T. et al., 2008, A&A, 485, 51 Google Scholar
Hughes, P. A., Aller, H. D. and Aller, M. F., 1985, ApJ, 298, 301 CrossRefGoogle Scholar
Koryukova, T. A. et al., 2022, MNRAS, 515, 1736 CrossRefGoogle Scholar
Kovalev, Y. Y. et al., 2005, AJ, 130, 2473 CrossRefGoogle Scholar
Kudryavtseva, N. A. et al., 2011, A&A, 526, A51 Google Scholar
Lin, D. N. C. and Shields, G. A., 1986, ApJ, 305, 28 CrossRefGoogle Scholar
Pushkarev, A. B. and Kovalev, Y. Y., 2015, MNRAS, 452, 4274 CrossRefGoogle Scholar
Richards, J. L. et al., 2011, ApJS, 194, 29 CrossRefGoogle Scholar