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arXiv · 2310.03791

VLASS tidal disruption events with optical flares I: the sample and a comparison to optically-selected TDEs

Jean J. Somalwar·Vikram Ravi·Dillon Z. Dong·Erica Hammerstein·Gregg Hallinan·Casey Law·Jessie Miller·Steven T. Myers·Yuhan Yao·Richard Dekany·Matthew Graham·Steven L. Groom·Josiah Purdum·Avery Wold
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Abstract

In this work, we use the Jansky VLA Sky Survey (VLASS) to compile the first sample of six radio-selected tidal disruption events (TDEs) with transient optical counterparts. While we still lack the statistics to do detailed population studies of radio-selected TDEs, we use these events to suggest trends in host galaxy and optical light curve properties that may correlate with the presence of radio emission, and hence can inform optically-selected TDE radio follow-up campaigns. We find that radio-selected TDEs tend to have faint and cool optical flares, as well as host galaxies with low SMBH masses. Our radio-selected TDEs also tend to have more energetic, larger radio emitting regions than radio-detected, optically-selected TDEs. We consider possible explanations for these trends, including by invoking super-Eddington accretion and enhanced circumnuclear media. Finally, we constrain the radio-emitting TDE rate to be $\gtrsim 10$ Gpc$^{-3}$ yr$^{-1}$.

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Jean J. Somalwar, Vikram Ravi, Dillon Z. Dong, Erica Hammerstein, Gregg Hallinan, Casey Law, Jessie Miller, Steven T. Myers, Yuhan Yao, Richard Dekany, Matthew Graham, Steven L. Groom, Josiah Purdum, Avery Wold. 2023-10-05. VLASS tidal disruption events with optical flares I: the sample and a comparison to optically-selected TDEs. https://arxiv.org/abs/2310.03791

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