TITLE: GCN CIRCULAR NUMBER: 43740 SUBJECT: GRB 260212A: Fermi GBM Observation DATE: 26/02/14 20:29:37 GMT FROM: eliza.neights@gmail.com Eliza Neights (GWU, NASA GSFC) and C. Meegan (UAH) report on behalf of the Fermi Gamma-ray Burst Monitor Team: "At 17:49:08.21 UT on 12 February 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260212A (trigger 792611353/260212742), which was also detected by Glowbug (Cheung et al. 2026, GCN 43719), SVOM/GRM (Zhang et al. 2026, GCN 43727), and GECAM-B (Zhang et al. 2026, GCN 43736). The angle from the Fermi LAT boresight is 127 degrees. The GBM light curve consists of multiple emission episodes with a duration (T90) of about 9.7 s (50-300 keV). The time-averaged spectrum from T0-1.5 to T0+14.5 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.66 +/- 0.02 and the cutoff energy, parameterized as Epeak, is 107 +/- 1 keV. The event fluence (10-1000 keV) in this time interval is (7.1 +/- 0.2)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0+8.7 s in the 10-1000 keV band is 16.2 +/- 0.6 ph/s/cm^2. A Band function fits the spectrum equally well with Epeak= 90 +/- 1 keV, alpha = -0.43 +/- 0.02 and beta = -2.52 +/- 0.04. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog: https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html For Fermi GBM data and info, please visit the official Fermi GBM Support Page: https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/" View this GCN Circular online at https://gcn.nasa.gov/circulars/43740. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...