GRB 230204B: GIT Discovery of a Fast Fading Afterglow Associated with an Energetic Gamma-Ray Burst from a Massive Star Progenitor
Year: 2026
Type: article
Abstract: We present a comprehensive multiwavelength study of a bright gamma-ray burst GRB 230204B, analyzing both prompt and afterglow emissions. This GRB is highly energetic, with an isotropic equivalent energy emission of E iso ∼ 2.2 × 10 54 erg released during the prompt emission. The GROWTH-India Telescope discovered a bright afterglow ( m r = 15.55) that fades rapidly (∝ t −1.82 ). The prompt emission shows a strong thermal photospheric emission along with a nonthermal high-energy component. We explore the evolution of these components and find them to be consistent with the theoretical expectations of the fireball model. Afterglow modeling reveals an energetic jet ( E γ ≳ 10 52 erg) expanding into a wind-type medium viewed nearly on-axis, suggesting a massive star progenitor with strong winds. We also explore correlations between the prompt emission and afterglow that may help to place GRB 230204B within the broader context of the long GRB population.
Source: The Astrophysical Journal
Authors: Vishwajeet Swain, Varun Bhalerao, Harsh Kumar, Mehul Goyal, Ankur Ghosh, Utkarsh Pathak, Poonam Chandra, Tomás Ahumada, G. C. Anupama, S. Bala, Sudhanshu Barway, Joshua S. Bloom, Dimple, Viraj Karambelkar, Mansi Kasliwal, Kuntal Misra, Josiah Purdum, Divita Saraogi, Jesper Sollerman, Aswin Suresh, Stéfan van der Walt, Gaurav Waratkar
Institutions: Indian Institute of Technology Bombay, Center for Astrophysics Harvard & Smithsonian, University of Johannesburg, National Radio Astronomy Observatory, California Institute of Technology, Indian Institute of Astrophysics, Universities Space Research Association, University of California, Berkeley, University of Birmingham, Aryabhatta Research Institute of Observational Sciences, Stockholm University, AlbaNova, Northwestern University
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $4,499
Funders: National Science Foundation, California Institute of Technology, Northwestern University, University of Warwick, Tata Institute of Fundamental Research, Department of Science and Technology, Ministry of Science and Technology, India, Indo-US Science and Technology Forum, Trinity College Dublin, Weizmann Institute of Science, Indian Institute of Technology Bombay, Stockholms Universitet, Deutsches Elektronen-Synchrotron, Science and Engineering Research Board, Institut National de Physique Nucléaire et de Physique des Particules
OpenAlex ID: W4417025110