GCN Circular 45747
GRB 260922A: Glowbug gamma-ray detection
From: C.C. Cheung at Naval Research Lab
Issued: 2026-09-25 17:04 UTC
Type: GRB, Gamma-ray Transient

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:

The Glowbug gamma-ray telescope [1,2,3], operating on the International Space Station, reports the detection of GRB 260922A, which was also detected by Swift/BAT (GCN 45690, 45703), CALET (GCN 45716), NuSTAR (GCN 45728), and Konus-Wind (GCN 45729)

Using an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2026-09-22 10:00:37.128 with a duration of 2.8 s and a total significance of about 14.9 sigma. The light curve comprises a single peak.

The analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS. Glowbug 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.

[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959
[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O
[3] Woolf, R.S. et al. 2024, Proc. SPIE, 13151, id. 1315108

Distribution Statement A: Approved for public release. Distribution is unlimited.

Filter: gamma-ray bursts are posted only if in the top 10% of the past year's — by fluence (total energy received per cm², from Fermi GBM, Konus-Wind, GECAM and similar circulars; now ≥ 3.9×10^-5 erg/cm²) or by the number of GCN Circulars about the burst (now ≥ 14). Thresholds are recalculated monthly.
Relayed automatically from NASA's General Coordinates Network.