{
  "eventId": "GRB 260410A",
  "editedBy": "Judith Racusin at NASA/GSFC <judith.racusin@nasa.gov> on behalf of C.C. Cheung at Naval Research Lab <Teddy.Cheung@nrl.navy.mil>",
  "format": "text/plain",
  "body": "C.C. Cheung, R. Woolf, M. Kerr, J.E. Grove (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge, D. Kocevski (MSFC), and M.S. Briggs (UAH) report:\n\nThe Glowbug gamma-ray telescope [1,2,3], operating on the International Space Station, reports the detection of GRB 260410A, which was detected by Fermi/GBM (GCN 44252, 44258), Fermi/LAT (GCN 44253), CALET (GCN 44283), Konus-Wind (GCN 44286), and Insight-HXMT/HE (GCN 44287).\n\nUsing an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2026-04-10 07:03:55.848 with a duration of 0.38 s and a total significance of about 46 sigma.  The light curve comprises an initial faint peak with a duration of ~25-ms, followed by a bright double-peaked structure with maxima at ~T0+0.13s and ~T0+0.24s.\n\nThe analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS.\n\nGlowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC.  It was launched on 2023 March 15 aboard the Department of Defense Space Test Program’s STP-H9 to the ISS and operated until 2024 April when it was put in safe storage on orbit. Glowbug was removed from storage and resumed operation on 2025 September 12.\n\n[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959\n[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O\n[3] Woolf, R.S. et al. 2024, Proc. SPIE, 13151, id. 1315108\n\nDistribution Statement A: Approved for public release.  Distribution is unlimited.",
  "subject": "GRB 260410A: Glowbug gamma-ray detection of a short burst",
  "circularId": 44290,
  "createdOn": 1776116999079,
  "submittedHow": "web",
  "submitter": "C.C. Cheung at Naval Research Lab <Teddy.Cheung@nrl.navy.mil>",
  "version": 2,
  "editedOn": 1776177676305,
  "bibcode": "2026GCN.44290....1C"
}