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arXiv · 2003.11280

The gamma-ray and Optical Variability Analysis of the BL Lac Object 3FGL J0449.4-4350

Xing Yang·Tingfeng Yi·Yan Zhang·Huaizhen Li·Lisheng Mao·Haiming Zhang·Li Ma
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Abstract

We have assembled the historical light curves of the BL Lac Object 3FGL J0449.4-4350 at optical and gamma-ray bands, the time spanning about 10 years, analyzed the periodic variability of the light curves by using four different methods (Lomb-Scargle periodogram, REDFIT38, Jurkevich and DACF). We detected a marginally possible quasi-periodic oscillation (QPO) of ~450 days. Assuming it originates from the helical motion jet in a supermassive binary black hole (SMBBH) system undergoing major merger, we estimate the primary black hole mass M~7.7*10^{9} M_sun. To explore the origin of the gamma-ray, we investigated the optical-gamma-ray correlations using discrete correlation function (DCF) method, and found that the correlation between the two bands is very significant. This strong correlation tends to imply lepton self-synchro-Compton (LSSC) model to produce the gamma-ray.

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Xing Yang, Tingfeng Yi, Yan Zhang, Huaizhen Li, Lisheng Mao, Haiming Zhang, Li Ma. 2020-03-25. The gamma-ray and Optical Variability Analysis of the BL Lac Object 3FGL J0449.4-4350. https://doi.org/10.1088/1538-3873%2Fab779e

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