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arXiv · 2209.07002

A 31.3 day Transient Quasiperiodic Oscillation in Gamma-ray Emission from Blazar S5 0716+714

Junping Chen·Tingfeng Yi·Yunlu Gong·Xing Yang·Zhihui Chen·Xin Chang·Lisheng Mao
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Abstract

We systematically search for quasiperiodic oscillatory (QPO) signals on the month timescale among the 1525 sources given in the Fermi Large Area Telescope Light Curve Repository. We find a transient QPO of 31.3$\pm$1.8 days in the gamma-ray band light curve of the TeV blazar S5 0716+714, which has seven cycles (MJD 55918-56137) for the first time by weighted wavelet Z-transform and Lomb-Scargle periodogram methods. Monte Carlo simulations based on the power spectral density and probability distribution function were used to evaluate the confidence level of the QPO, and the result is $\sim 4.1σ$. Seasonal autoregressive integrated moving average modeling of the light curve revealed it is a significant physical QPO. The physical models to explain the sporadic QPO of the month-timescale QPOs in blazar were discussed. Our studies indicate that the helical jet model and blob move helically in a curved jet model to properly explain this kind of transient QPO.

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Junping Chen, Tingfeng Yi, Yunlu Gong, Xing Yang, Zhihui Chen, Xin Chang, Lisheng Mao. 2022-10-17. A 31.3 day Transient Quasiperiodic Oscillation in Gamma-ray Emission from Blazar S5 0716+714. https://doi.org/10.3847/1538-4357%2Fac91c3

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