TITLE: GCN CIRCULAR NUMBER: 16617 SUBJECT: GRB 140721A: Fermi GBM detection DATE: 14/07/21 16:18:54 GMT FROM: Hoi-Fung Yu at MPE H.-F. Yu (MPE) reports on behalf of the Fermi GBM Team: "At 08:03:22.32 UT on 21 July 2014, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 140721A (trigger 427622605 / 140721336). The on-ground calculated location, using the GBM trigger data, is RA = 175.7, Dec = -41.2 (J2000 degrees, equivalent to 11h 42m 48s, -41d 12'), with an uncertainty of 1.0 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 118 degrees. The GBM light curve shows a multi-pulse feature with a duration (T90) of about 128 s (50-300 keV). The time-averaged spectrum from T0-6.400 s to T0+84.737 s is well fit by a Band function with Epeak = 129.0 +/- 10.2 keV, alpha = -1.05 +/- 0.05, and beta = -1.98 +/- 0.03. The event fluence (10-1000 keV) in this time interval is (4.95 +/- 0.08)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+18.752 s in the 10-1000 keV band is 14.0 +/- 0.5 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."