SVOM false alarm due to Crab coding noise

AI Summary

Initial detection of GRB 260913A by SVOM/ECLAIRs was later retracted as a false alarm caused by coding noise from the Crab. Optical follow-up did not detect any source within expected parameters.

Measurements

Notices (1)

SVOM — GRB · Sun, 13 Sep 2026 07:38:11 GMT

GCN Circulars (3)

GCN-45561 — GRB 260913A · Mon, 14 Sep 2026 08:34:42 GMT
The SVOM mission team has retracted the classification of GRB 260913A as an astrophysical event, determining it was caused by coding noise from the Crab in the field of view. The initial alert, issued on 2026-09-13, has been corrected after reprocessing the data.

GCN-45558 — GRB 260913A · Sun, 13 Sep 2026 16:19:08 GMT
The SVOM/C-GFT team observed the field of GRB 260913A approximately 6.83 hours after the initial detection by SVOM/ECLAIRs. No credible optical candidate was found within the error box, with upper limits measured in g, r, and i bands as 20.3, 20.2, and 20.1 AB magnitudes respectively.

GCN-45557 — GRB 260913A · Sun, 13 Sep 2026 08:42:43 GMT
The SVOM mission detected a faint gamma-ray burst, GRB 260913A, on September 13, 2026, at 07:38:21 UTC. The burst was localized to RA 105.2715, Dec 58.8936 degrees with a 90% confidence level radius of 9.50 arcmin, but no immediate slew was performed due to low detection significance and solar angle constraints.