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arXiv · 2404.13326

Two-component off-axis jet model for radio flares of tidal disruption events

Yuri Sato·Kohta Murase·Mukul Bhattacharya·Jose Carpio·Mainak Mukhopadhyay·B. Theodore Zhang
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Abstract

Recently, radio emission from tidal disruption events (TDEs) has been observed from months to years after the optical discovery. Some of the TDEs including ASASSN-14ae, ASASSN-15oi, AT 2018hyz, and AT 2019dsg are accompanied by the late-time rebrightening phase characterized by a rapid increase in the radio flux. We show that it can be explained by the off-axis two-component jet model, in which the late-time rebrightening arises from the off-axis view of a decelerating narrower jet with an initial Lorentz factor of ~10 and a jet opening angle of ~0.1 rad, while the early-time radio emission is attributed to the off-axis view of a wider jet component. We also argue that the rate density of jetted TDEs inferred from these events is consistent with the observations.

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Yuri Sato, Kohta Murase, Mukul Bhattacharya, Jose Carpio, Mainak Mukhopadhyay, B. Theodore Zhang. 2024-04-20. Two-component off-axis jet model for radio flares of tidal disruption events. https://doi.org/10.1103/physrevd.110.l061307

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