General information
GRB 260523A was reported by Fermi/GBM as a likely long GRB triggering at 2026-05-23 16:06:10 UT with a broad real-time localization. MASTER-Net reported optical follow-up observations hours later with only upper limits; a GECAM-B circular in this packet discusses GRB 260523B, introducing an association/name ambiguity.
Wavelength coverage
- Gamma-ray / hard X-ray: Fermi/GBM detection and localization; GECAM-B reports detection in ~70–6000 keV (but for GRB 260523B per the circular text).
- Optical: MASTER-Kislovodsk clear-filter imaging with limits ~18.1–18.5 mag.
No observations mentioned in: radio, infrared, ultraviolet, soft X-ray.
Lightcurve and spectrum
Redshift
What’s special vs typical