GRB 230204B: GIT Discovery of a Fast Fading Afterglow Associated with an Energetic Gamma-Ray Burst from a Massive Star Progenitor

Abstract

Copyright and License

© 2026. 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 the comments and suggestions that have helped us to improve the paper.

We thank all the people from the GROWTH collaboration for the observation.

GIT (H. Kumar et al. 2022) is a 70 cm telescope with a 07 field of view, set up by the Indian Institute of Astrophysics (IIA) and the Indian Institute of Technology Bombay (IITB) with funding from DST-SERB and IUSSTF. It is located at the Indian Astronomical Observatory (Hanle), operated by IIA. We acknowledge funding by the IITB alumni batch of 1994, which partially supports the operations of the telescope. Telescope technical details are available at https://sites.google.com/view/growthindia/.

The National Radio Astronomy Observatory and Green Bank Observatory are facilities of the U.S. National Science Foundation operated under cooperative agreement by Associated Universities, Inc. We thank the staff of the GMRT who made these observations possible. GMRT is run by the National Centre for Radio Astrophysics of the Tata Institute of Fundamental Research.

Based on observations obtained with the Samuel Oschin Telescope 48 inch and the 60 inch Telescope at the Palomar Observatory as part of the ZTF project. ZTF is supported by the National Science Foundation under Grant No. AST-2034437 and a collaboration including Caltech, IPAC, the Weizmann Institute of Science, the Oskar Klein Center at Stockholm University, the University of Maryland, Deutsches Elektronen-Synchrotron and Humboldt University, the TANGO Consortium of Taiwan, the University of Wisconsin at Milwaukee, Trinity College Dublin, Lawrence Livermore National Laboratories, IN2P3, University of Warwick, Ruhr University Bochum, Cornell University, and Northwestern 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.

We also acknowledge the Zenodo repository for sharing our data products.

Facilities

MAXI - JAXA Monitor of All-sky X-ray Image experiment (GSC), Fermi - Fermi Gamma-Ray Space Telescope (formerly GLAST) (GBM), Astrosat - (CZTI), Swift - Swift Gamma-Ray Burst Mission (XRT), GIT - , PO:1.5m - Palomar Observatory's 1.5 meter Telescope (Palomar 60 inch telescope), GMRT - Giant Meter-wave Radio Telescope, VLA - Very Large Array.

Software References

astropy (Astropy Collaboration et al. 2013, 2018, 2022), Source Extractor (E. Bertin & S. Arnouts 1996), Astro-SCRAPPY (C. McCully & M. Tewes 2019), solve-field astrometry engine (D. Lang et al. 2010), PSFEx (E. Bertin 2013), ThreeML (G. Vianello et al. 2015), GDT-Fermi (A. Goldstein et al. 2023).