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arXiv · 2412.10771

Revisiting radio variability of the blazar 3C 454.3

Ashutosh Tripathi·Alok C. Gupta·Krista Lynne Smith·Paul J. Wiita·Margo F. Aller·Alexandr E. Volvach·Anne Lähteenmäki·Hugh D. Aller·Merja Tornikoski·Larisa N. Volvach
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Abstract

We examine lengthy radio light curves of the flat spectrum radio galaxy 3C 454.3 for possible quasi-periodic oscillations (QPOs). The data used in this work were collected at five radio frequencies, 4.8, 8.0, 14.5, 22.0, and 37.0 GHz between 1979--2013 as observed at the University of Michigan Radio Astronomical Observatory, Crimean Astrophysical Observatory, and Aalto University Mets{\"a}hovi Radio Observatory. We employ generalized Lomb-Scargle periodogram and weighted wavelet transform analyses to search for periodicities in these light curves. We confirm a QPO period of $\sim$ 2000 day to be at least 4$\sigma$ significant using both methods at all five radio frequencies between 1979 and 2007, after which a strong flare changed the character of the light curve. We also find a $\sim$~600 day period which is at least 4$\sigma$ significant, but only in the 22.0 and 37.0 GHz light curves. We briefly discuss physical mechanisms capable of producing such variations.

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Ashutosh Tripathi, Alok C. Gupta, Krista Lynne Smith, Paul J. Wiita, Margo F. Aller, Alexandr E. Volvach, Anne Lähteenmäki, Hugh D. Aller, Merja Tornikoski, Larisa N. Volvach. 2024-12-14. Revisiting radio variability of the blazar 3C 454.3. https://doi.org/10.3847/1538-4357%2Fad90e3

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