TITLE: GCN CIRCULAR NUMBER: 14674 SUBJECT: GRB 130518A: Fermi GBM detection DATE: 13/05/18 20:52:02 GMT FROM: Shaolin Xiong at UAH Shaolin Xiong (UAH) reports on behalf of the Fermi GBM Team: "At 13:54:37.53 UT on 18 May 2013, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 130518A (trigger 390578080 / 130518580). High peak flux from the GRB caused GBM to issue a repoint request, but the spacecraft did not slew to this burst due to the Solar TOO. The on-ground calculated location, using the GBM trigger data, is RA = 355.88, DEC = 46.05 (J2000 degrees, equivalent to 23 h 43 m, 46 d 03 '), with an uncertainty of 1 degrees (radius, 1-sigma containment, statistical only; there is additionally a systematic error which is currently estimated to be 2 to 3 degrees). The angle from the Fermi LAT boresight is 43 degrees. The GBM light curve consists of several pulses with a duration (T90) of about 48 s (50-300 keV). The time-averaged spectrum from T0+10 s to T0+60 s is adequately fit by a Band function with Epeak = 396 +/- 9 keV, alpha = -0.86 +/- 0.01, and beta = -2.27 +/- 0.04. The event fluence (10-1000 keV) in this time interval is (9.3 +/- 0.06)E-5 erg/cm^2. The 1-sec peak photon flux measured starting from T0+25.6 s in the 10-1000 keV band is 45.4 +/- 0.4 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."