_version_ 1866915770816004096
author Wise, Jacob L.
Perley, Daniel A.
Sarin, Nikhil
Matsumoto, Tatsuya
Hinds, K-Ryan
Yao, Yuhan
Sollerman, Jesper
Schulze, Steve
Bochenek, Aleksandra
Coughlin, Michael W.
De, Kishalay
Dekany, Richard
Frederick, Sara
Fremling, Christoffer
Gezari, Suvi
Graham, Matthew J.
Ho, Anna Y. Q.
Kulkarni, Shrinivas
Laher, Russ R.
Omand, Conor
Johnson, Natalya
Sharma, Yashvi
Taggart, Kirsty
Ward, Charlotte
Wold, Avery
Yan, Lin
author_facet Wise, Jacob L.
Perley, Daniel A.
Sarin, Nikhil
Matsumoto, Tatsuya
Hinds, K-Ryan
Yao, Yuhan
Sollerman, Jesper
Schulze, Steve
Bochenek, Aleksandra
Coughlin, Michael W.
De, Kishalay
Dekany, Richard
Frederick, Sara
Fremling, Christoffer
Gezari, Suvi
Graham, Matthew J.
Ho, Anna Y. Q.
Kulkarni, Shrinivas
Laher, Russ R.
Omand, Conor
Johnson, Natalya
Sharma, Yashvi
Taggart, Kirsty
Ward, Charlotte
Wold, Avery
Yan, Lin
contents We present optical/UV photometric and spectroscopic observations, as well as X-ray and radio follow-up, of the extraordinary event AT2019cmw. With a peak bolometric luminosity of ~$\mathrm{10^{45.6}\,erg\,s^{-1}}$, it is one of the most luminous thermal transients ever discovered. Extensive spectroscopic follow-up post-peak showed only a featureless continuum throughout its evolution. This, combined with its nuclear location, blue colour at peak and lack of prior evidence of an AGN in its host lead us to interpret this event as a `featureless' tidal disruption event (TDE). It displays photometric evolution atypical of most TDEs, cooling from ~30 kK to ~10 kK in the first ~300 days post-peak, with potential implications for future photometric selection of candidate TDEs. No X-ray or radio emission is detected, placing constraints on the presence of on-axis jetted emission or a visible inner-accretion disk. Modelling the optical light curve with existing theoretical prescriptions, we find that AT2019cmw may be the result of the disruption of a star in the tens of solar masses by a supermassive black hole (SMBH). Combined with a lack of detectable star formation in its host galaxy, it could imply the existence of a localised region of star formation around the SMBH. This could provide a new window to probe nuclear star formation and the shape of the initial mass function (IMF) in close proximity to SMBHs out to relatively high redshifts.
format Preprint
id arxiv_https___arxiv_org_abs_2507_07380
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle AT2019cmw: A highly luminous, cooling featureless TDE candidate from the disruption of a high mass star in an early-type galaxy
Wise, Jacob L.
Perley, Daniel A.
Sarin, Nikhil
Matsumoto, Tatsuya
Hinds, K-Ryan
Yao, Yuhan
Sollerman, Jesper
Schulze, Steve
Bochenek, Aleksandra
Coughlin, Michael W.
De, Kishalay
Dekany, Richard
Frederick, Sara
Fremling, Christoffer
Gezari, Suvi
Graham, Matthew J.
Ho, Anna Y. Q.
Kulkarni, Shrinivas
Laher, Russ R.
Omand, Conor
Johnson, Natalya
Sharma, Yashvi
Taggart, Kirsty
Ward, Charlotte
Wold, Avery
Yan, Lin
High Energy Astrophysical Phenomena
We present optical/UV photometric and spectroscopic observations, as well as X-ray and radio follow-up, of the extraordinary event AT2019cmw. With a peak bolometric luminosity of ~$\mathrm{10^{45.6}\,erg\,s^{-1}}$, it is one of the most luminous thermal transients ever discovered. Extensive spectroscopic follow-up post-peak showed only a featureless continuum throughout its evolution. This, combined with its nuclear location, blue colour at peak and lack of prior evidence of an AGN in its host lead us to interpret this event as a `featureless' tidal disruption event (TDE). It displays photometric evolution atypical of most TDEs, cooling from ~30 kK to ~10 kK in the first ~300 days post-peak, with potential implications for future photometric selection of candidate TDEs. No X-ray or radio emission is detected, placing constraints on the presence of on-axis jetted emission or a visible inner-accretion disk. Modelling the optical light curve with existing theoretical prescriptions, we find that AT2019cmw may be the result of the disruption of a star in the tens of solar masses by a supermassive black hole (SMBH). Combined with a lack of detectable star formation in its host galaxy, it could imply the existence of a localised region of star formation around the SMBH. This could provide a new window to probe nuclear star formation and the shape of the initial mass function (IMF) in close proximity to SMBHs out to relatively high redshifts.
title AT2019cmw: A highly luminous, cooling featureless TDE candidate from the disruption of a high mass star in an early-type galaxy
topic High Energy Astrophysical Phenomena
url https://arxiv.org/abs/2507.07380