A Luminous and Hot Infrared through X-Ray Transient at a 5 kpc Offset from a Dwarf Galaxy

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 would like to thank the referee for the valuable comments on the manuscript. We would like to thank Stella Ocker for the use of her WIRC time. We would like to thank Eliot Quataert and Xiaoshan Huang for useful discussions.

This research is based on observations made with the NASA/ESA Hubble Space Telescope obtained from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5–26555. These observations are associated with program 17854.

Some/all of the data presented in this paper were obtained from the Mikulski Archive for Space Telescopes (MAST) at the Space Telescope Science Institute. The specific observations analyzed can be accessed via doi:10.17909/3kvv-bv86.

This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester.

This work is 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.

The ZTF forced-photometry service was funded under the Heising-Simons Foundation grant #12540303 (PI: Graham).

The Gordon and Betty Moore Foundation, through both the Data-Driven Investigator Program and a dedicated grant, provided critical funding for SkyPortal.

SED Machine is based upon work supported by the National Science Foundation under grant No. 1106171.

Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation.

The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain.

This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under grant No. DGE-1745301. M.W.C. acknowledges support from the National Science Foundation with grant Nos. PHY-2010970 and OAC-2117997. 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.

P.N. acknowledges support from the Gordon and Betty Moore Foundation and the John Templeton Foundation that fund the Black Hole Initiative (BHI) at Harvard University where she serves as an external PI.

M.W.C. acknowledges support from the National Science Foundation with grant Nos. PHY-2308862 and PHY-2117997.

Facilities

ATLAS - , HST - Hubble Space Telescope satellite (WFC3, ACS), VLA - Very Large Array, Keck:1 - , Keck:2 - , Hale - Palomar Observatory's 5.1m Hale Telescope, XMM - Newton X-Ray Multimirror Mission satellite, LDT - , HEASARC - , Swift - Swift Gamma-Ray Burst Mission, NuSTAR - The NuSTAR (Nuclear Spectroscopic Telescope Array) mission, PS1 - Panoramic Survey Telescope and Rapid Response System Telescope #1 (Pan-STARRS), IRAM:NOEMA - .

Software References

astropy (The Astropy Collaboration et al. 2018, 2022; T. P. Robitaille et al. 2013), scipy (P. Virtanen et al. 2020), emcee (D. Foreman-Mackey et al. 2013), dynesty (J. S. Speagle 2020), MOSFIT (J. Guillochon et al. 2018), numpy (S. Van Der Walt et al. 2011; C. R. Harris et al. 2020), linetools, photutils (L. Bradley et al. 2025), casa (CASA Team et al. 2022), lpipe (D. A. Perley 2019), spectres (A. C. Carnall & C. A. Carnall 2017), prospector (B. D. Johnson et al. 2021), fsps (C. Conroy et al. 2010), python-fsps (B. Johnson et al. 2024), sfdmap, swifttools,²³ heasoft (NASA High Energy Astrophysics Science Archive Research Center (HEASARC) 2014), extinction, sedpy (D. B. Johnson 2019), statsmodels (S. Seabold & J. Perktold 2010), scamp (C. Gabriel et al. 2006), swarp (E. Bertin 2010).