STARITHM
Short GRB 261009A detected by Fermi GBM with 3.2° localization
AI Summary
Fermi GBM detected a likely short gamma-ray burst (GRB 261009A) on October 9, 2026, at 22:19:11 UT, with trigger ID 813277156. The burst was localized to RA = 116.9°, Dec = 45.5° (J2000) with a statistical uncertainty of 3.2 degrees and a burst significance of 10.2 sigma. The event showed a hardness ratio of 1.53 and duration of ~0.256 seconds, consistent with a short GRB classification, though early flight-based classification suggested AGN contamination (85% probability). Ground-based refinement and LAT positioning (12° from boresight) support the GRB interpretation.
Measurements
| Event ID | 813277156 |
|---|---|
| Source | Fermi GBM |
| Alert type | GRB |
| Significance | high |
| Trigger time (UTC) | Fri, 09 Oct 2026 22:19:11 GMT |
| Right ascension (J2000) | 116.95° |
| Declination (J2000) | 45.5° |
| Position error radius | 3.16° |
| GCN notices | 4 |
| GCN circulars | 1 |
Notices (1)
Fermi GBM — GRB · Fri, 09 Oct 2026 22:19:11 GMT
GCN Circulars (1)
GCN-45879 — GRB 261009A
· Fri, 09 Oct 2026 22:29:42 GMT
The Fermi Gamma-ray Burst Monitor (GBM) detected a likely short gamma-ray burst (GRB) designated GRB 261009A on October 9, 2026, at 22:19:11 UT. The event was localized to RA = 116.9, Dec = 45.5 (J2000) with a statistical uncertainty of 3.2 degrees.
AI summary generated Sat, 10 Oct 2026 03:26:38 GMT.