Year: 2025
Type: article
Abstract: ABSTRACT Gamma-ray bursts are the most luminous electromagnetic events in the Universe. Their prompt gamma-ray emission has typical durations between a fraction of a second and several minutes. A rare subset of these events have durations in excess of a thousand seconds, referred to as ultra-long gamma-ray bursts. Here, we report the discovery of the longest gamma-ray burst ever seen with a $\sim$25 000 s gamma-ray duration, GRB 250702B, and characterize this event using data from four instruments in the InterPlanetary Network and the Monitor of All-sky X-ray Image. We find a hard spectrum, subsecond variability, and high total energy, which are only known to arise from ultrarelativistic jets powered by a rapidly spinning stellar-mass central engine. These properties and the extreme duration are together incompatible with all confirmed gamma-ray burst progenitors and nearly all models in the literature. This burst is naturally explained with the helium merger model, where a field binary ends when a black hole falls into a stripped star and proceeds to consume and explode it from within. Under this paradigm, GRB 250702B adds to the growing evidence that helium stars expand and that some ultra-long GRBs have similar evolutionary pathways as collapsars, stellar-mass gravitational wave sources, and potentially rare types of supernovae.
Authors: Eliza Neights, Eric Burns, Chris L Fryer, Dmitry Svinkin, Suman Bala, Rachel Hamburg, Ramandeep Gill, Michela Negro, Megan Masterson, James DeLaunay, David J Lawrence, Sophie E D Abrahams, Yuta Kawakubo, Paz Beniamini, Christian Aa Diget, Dmitry Frederiks, John Goldsten, Adam Goldstein, Alexander D Hall-Smith, Erin Kara, Alison M Laird, Gavin P Lamb, Oliver J Roberts, Ryan Seeb, V Ashley Villar, Aldana Holzmann Airasca, Joseph R Barber, P Narayana Bhat, Elisabetta Bissaldi, Michael S Briggs, William H Cleveland, Sarah Dalessi, Davide Depalo, Misty M Giles, Jonathan Granot, Boyan A Hristov, C Michelle Hui, Andreas von Kienlin, Carolyn Kierans, Daniel Kocevski, Stephen Lesage, Alexandra L Lysenko, Bagrat Mailyan, Christian Malacaria, Oindabi Mukherjee, Tyler Parsotan, Anna Ridnaia, Samuele Ronchini, Lorenzo Scotton, Aaron C Trigg, Anastasia Tsvetkova, Mikhail Ulanov, Péter Veres, Maia Williams, Colleen A Wilson-Hodge, Joshua Wood
Institutions: Goddard Space Flight Center, George Washington University, Louisiana State University, Los Alamos National Laboratory, Ioffe Institute, Universities Space Research Association, Open University of Israel, Universidad Nacional Autónoma de México, Massachusetts Institute of Technology, Pennsylvania State University, Johns Hopkins University, Johns Hopkins University Applied Physics Laboratory, University of York, Aoyama Gakuin University, Liverpool John Moores University, Marshall Space Flight Center, Brown University, Center for Astrophysics Harvard & Smithsonian, The NSF AI Institute for Artificial Intelligence and Fundamental Interactions, University of Trento, Istituto Nazionale di Fisica Nucleare, Sezione di Bari, Amentum (United States), University of Alabama in Huntsville, Polytechnic University of Bari, Max Planck Institute for Extraterrestrial Physics, Florida Institute of Technology, Astronomical Observatory of Rome, National Institute for Astrophysics, Gran Sasso Science Institute, University of Cagliari, Northwestern University
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,046
Funders: National Aeronautics and Space Administration, Oak Ridge Associated Universities, Johns Hopkins University, Royal Society, United States-Israel Binational Science Foundation, Nuclear Safety and Security Commission, Israel Science Foundation, Ioffe Institute, Jet Propulsion Laboratory, Marshall Space Flight Center, Office of STEM Engagement, Science and Technology Facilities Council
OpenAlex ID: W4416227766