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arXiv · 2306.10248

Multi-wavelength temporal variability of the blazar PKS 1510-089

Q. Yuan·Pankaj Kushwaha·Alok C. Gupta·Ashutosh Tripathi·Paul J. Wiita·M. Zhang·X. Liu·Anne Lahteenmaki·Merja Tornikoski·Joni Tammi·Venkatessh Ramakrishnan·L. Cui·X. Wang·M. F. Gu·Cosimo Bambi·A. E. Volvach
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Abstract

We perform correlation and periodicity search analyses on long-term multi-band light curves of the FSRQ 1510-089 observed by the space-based Fermi--Large Area Telescope in gamma-rays, the SMARTS and Steward Observatory telescopes in optical and near-infrared (NIR) and the 13.7 m radio telescope in Metsahovi Radio Observatory between 2008 and 2018. The z-transform discrete correlation function method is applied to study the correlation and possible time lags among these multi band light curves. Among all pairs of wavelengths, the gamma-ray vs. optical/NIR and optical vs. NIR correlations show zero time lags; however, both the gamma-ray and optical/NIR emissions precede the radio radiation. The Generalized Lomb-Scargle periodogram, Weighted Wavelet Z-transform, and REDFIT techniques are employed to investigate the unresolved-core-emission dominated 37 GHz light curve and yield evidence for a quasi-period around 1540 days, although given the length of the whole data set it cannot be claimed to be significant. We also investigate the optical/NIR color variability and find that this source shows a simple redder-when-brighter behavior over time, even in the low flux state.

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Q. Yuan, Pankaj Kushwaha, Alok C. Gupta, Ashutosh Tripathi, Paul J. Wiita, M. Zhang, X. Liu, Anne Lahteenmaki, Merja Tornikoski, Joni Tammi, Venkatessh Ramakrishnan, L. Cui, X. Wang, M. F. Gu, Cosimo Bambi, A. E. Volvach. 2023-06-17. Multi-wavelength temporal variability of the blazar PKS 1510-089. https://doi.org/10.3847/1538-4357%2Facdd74

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