TITLE: GCN CIRCULAR NUMBER: 13444 SUBJECT: GRB 120711A: Fermi LAT detection DATE: 12/07/11 17:29:37 GMT FROM: Thomas P.H. Tam at Nat.Tsing Hua U. P.H.T. Tam, K.L. Li and A.K.H. Kong (NTHU) report: We report on the Fermi Large Area Telescope (LAT) detection of >100 MeV gamma-ray emission from the direction of the bright GRB 120711A, which triggered INTEGRAL (Gotz et al., GCN 13434), MAXI/GSC (Serino et al., GCN 13436), and Fermi/GBM (Gruber et al., GCN 13437). The GRB position was outside the LAT field of view at the GRB onset (c.f. GCN 13437). However, gamma-ray emission up to around 2 GeV was detected from the GRB direction from 0.8 ks to ~7 ks after the burst. Such duration is one of the longest ever observed for a GRB in GeV domain. Using the data obtained from the above period, an unbinned likelihood analysis resulted in a detection significance of ~7 sigma, and a photon spectral index of -1.8+-0.3. We localized the LAT emission to be at RA, DEC (J2000 deg) = 94.58, -70.93, with a statistical error of ~0.17 deg (68% CL), which is compatible with the Swift/XRT position (Beardmore et al., GCN 13442).