Logo image
AT2019cmw: a highly luminous, cooling featureless TDE candidate from the disruption of a high mass star in an early-type galaxy
Journal article   Open access   Peer reviewed

AT2019cmw: a highly luminous, cooling featureless TDE candidate from the disruption of a high mass star in an early-type galaxy

Jacob L. Wise, Daniel A. Perley, Nikhil Sarin, Tatsuya Matsumoto, K-Ryan Hinds, Yuhan Yao, Jesper Sollerman, Steve Schulze, Aleksandra Bochenek, Michael W. Coughlin, …
Monthly notices of the Royal Astronomical Society, v 546(3), 130
01 Mar 2026
url
https://doi.org/10.1093/mnras/stag130View
Published, Version of Record (VoR) Open

Abstract

Astronomy & Astrophysics Science & Technology Physical Sciences
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 similar to 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 similar to 30 to similar to 10kK in the first similar to 300 d 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 disc. 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 localized 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.

Metrics

Details

Logo image