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arXiv · 2305.03767

Probing the Sub-Parsec Dust of a Supermassive Black Hole with the Tidal Disruption Event AT 2020mot

Megan Newsome·Iair Arcavi·D. A. Howell·Jamison Burke·Yael Dgany·Joseph Farah·Sara Faris·Daichi Hiramatsu·Curtis McCully·Estefania Padilla-Gonzalez·Craig Pellegrino·Giacomo Terreran
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Abstract

AT 2020mot is a typical UV/optical tidal disruption event (TDE) with no radio or X-ray signatures in a quiescent host. We find an i-band excess and re-brightening along the decline of the light curve which could be due to two consecutive dust echoes from a TDE. We model our observations following van Velzen et al. (2016) and find that the near-infrared light curve can be explained by concentric rings of thin dust within $\sim$0.1 parsecs of a 6e6 M$_{\odot}$ supermassive black hole (SMBH), among the smallest scales at which dust has been inferred near SMBHs. We find dust covering factors of order fc $\leq$ 2%, much lower than found for dusty tori of active galactic nuclei. These results highlight the potential of TDEs for uncovering the environments around black holes when including near-infrared observations in high-cadence transient studies.

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Megan Newsome, Iair Arcavi, D. A. Howell, Jamison Burke, Yael Dgany, Joseph Farah, Sara Faris, Daichi Hiramatsu, Curtis McCully, Estefania Padilla-Gonzalez, Craig Pellegrino, Giacomo Terreran. 2023-05-05. Probing the Sub-Parsec Dust of a Supermassive Black Hole with the Tidal Disruption Event AT 2020mot. https://arxiv.org/abs/2305.03767

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