A Massive Black Hole 0.8 kpc from the Host Nucleus Revealed by the Offset Tidal Disruption Event AT2024tvd

Abstract

Copyright and License

© 2025. The Author(s). Published by the American Astronomical Society.

Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

Acknowledgement

We thank the anonymous referee for providing constructive comments and suggestions. Y.Y. would like to thank Angelo Ricarte, Anil Seth, and Nick Stone for helpful conversations about the origin and search of offset MBHs. C.W. would like to thank Peter Melchior for helpful discussions about running Scarlet on HST imaging. We thank Kirsty Taggart for assistance with the Kast data reduction.

C.W. acknowledges support from the LSST Discovery Alliance under grant AWD1008640. R.M. acknowledges support by the National Science Foundation under award No. AST-2224255. C.L., A.A.M., and N.R. are supported by DoE award No. DE-SC0025599. K.D.A. acknowledges support provided by the NSF through award AST-2307668. M.N. is supported by the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement No. 948381) and by UK Space Agency grant No. ST/Y000692/1.

Based on observations obtained with the Samuel Oschin Telescope 48-inch and the 60-inch Telescope at the Palomar Observatory as part of the Zwicky Transient Facility project. ZTF is supported by the National Science Foundation under grant No. AST-2034437 and a collaboration including Caltech, IPAC, the Oskar Klein Center at Stockholm University, the University of Maryland, University of California, Berkeley, the University of Wisconsin at Milwaukee, University of Warwick, Ruhr University Bochum, Cornell University, Northwestern University, and Drexel University. Operations are conducted by COO, IPAC, and UW. SED Machine is based upon work supported by the National Science Foundation under grant No. 1106171. The Gordon and Betty Moore Foundation, through both the Data-Driven Investigator Program and a dedicated grant, provided critical funding for SkyPortal. The ZTF forced-photometry service was funded under the Heising-Simons Foundation grant No. 12540303 (PI: Graham).

This work has made use of data from the Asteroid Terrestrial-impact Last Alert System (ATLAS) project. The ATLAS project is primarily funded to search for near earth asteroids through NASA grants NN12AR55G, 80NSSC18K0284, and 80NSSC18K1575; byproducts of the NEO search include images and catalogs from the survey area. This work was partially funded by Kepler/K2 grant J1944/80NSSC19K0112 and HST GO-15889, and STFC grants ST/T000198/1 and ST/S006109/1. The ATLAS science products have been made possible through the contributions of the University of Hawaii Institute for Astronomy, the Queen's University Belfast, the Space Telescope Science Institute, the South African Astronomical Observatory, and The Millennium Institute of Astrophysics (MAS), Chile.

The scientific results reported in this Letter are based on observations made by the Chandra X-ray Observatory.

This work uses data obtained with eROSITA telescope on board the SRG observatory. The SRG observatory was built by Roskosmos with the participation of the Deutsches Zentrum für Luft- und Raumfahrt (DLR). The SRG/eROSITA X-ray telescope was built by a consortium of German Institutes led by MPE, and supported by DLR. The SRG spacecraft was designed, built, launched, and is operated by the Lavochkin Association and its subcontractors. The science data were downlinked via the Deep Space Network Antennae in Bear Lakes, Ussurijsk, and Baykonur, funded by Roskosmos. The eROSITA data used in this work were processed using the eSASS software system developed by the German eROSITA consortium and proprietary data reduction and analysis software developed by the Russian eROSITA Consortium.

MMT Observatory and Zwicky Transient Facility access was supported by Northwestern University and the Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA).

The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.

Facilities

PO:1.2m - Palomar Observatory's 1.2 meter Samuel Oschin Telescope, PO:1.5m - Palomar Observatory's 1.5 meter Telescope, Shane - Lick Observatory's 3m Shane Telescope, MMT - MMT at Fred Lawrence Whipple Observatory, Swift - Swift Gamma-Ray Burst Mission, EVLA - Expanded Very Large Array, CXO - Chandra X-ray Observatory satellite, ATLAS - , VLA - Very Large Array.

Software References

astropy (Astropy Collaboration et al. 2013), CASA (J. P. McMullin et al. 2007), emcee (D. Foreman-Mackey et al. 2013), heasoft (Heasarc 2014), matplotlib (J. D. Hunter 2007), Scarlet (P. Melchior et al. 2018), Scarlet2 (M. Sampson et al. 2024; C. Ward et al. 2025), scipy (P. Virtanen et al. 2020), xspec (K. A. Arnaud 1996).