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arXiv · 2203.02168

A Possible 3-Year Quasi-Periodic Oscillation in {\gamma}-Ray Emission from the FSRQ S5 1044+71

G. G. Wang·J. T. Cai·J. H. Fan
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Abstract

Variability is a typical observation feature of Fermi blazars, sometimes it shows quasi-periodic oscillation (QPO). In this work, we obtained 5-day binned light curves (with a time coverage of $\sim$ 12.9 yr) for S5 1044+71 based on Fermi LAT data, adopted five different methods: Date-compensated Discrete Fourier Transform (DCDFT), Jurkevich (JV), Lomb-Scargle Periodogram (LSP), a Fortran 90 program (REDFIT) and the Weighted Wavelet Z-transform (WWZ) to the $\gamma$-ray light curve, and found a possible QPO of 3.06 $\pm$ 0.43 yr at the significance level of $\sim3.6\sigma$. A binary black hole model including accretion model and dual-jets model is used to explain this quasi-periodic variability. We also estimated the Doppler factors and the apparent velocity for the two jet components. We speculate that this $\gamma$-ray quasi-periodic modulation suggest the presence of a binary supermassive black hole in S5 1044+71.

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G. G. Wang, J. T. Cai, J. H. Fan. 2022-03-04. A Possible 3-Year Quasi-Periodic Oscillation in {\gamma}-Ray Emission from the FSRQ S5 1044+71. https://doi.org/10.3847/1538-4357%2Fac5b08

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