TITLE: GCN CIRCULAR NUMBER: 16363 SUBJECT: GRB 140606B: Fermi GBM detection DATE: 14/06/07 16:05:57 GMT FROM: Eric Burns at U of Alabama E. Burns (UAH) reporting on behalf of the Fermi GBM Team: "At 03:11:51.86 UT on 06 June 2014, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 140606B (trigger 423717114 / 140606133). The on-ground calculated location, using the GBM trigger data, is RA = 327.9, DEC = +33.7 (J2000 degrees, equivalent to 21 h 51 m, 33 d 41 '), with an uncertainty of 1.00 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 66 degrees. The optical afterglow candidates reported by iPTF (Singer et al. GCN 16360) lie within the 1-sigma (statistical and systematic) uncertainty regions surrounding the GBM localization. The GBM light curve shows one long peak with a noisy tail with a duration (T90) of about 23.6 s (50-300 keV). The time-averaged spectrum from T0-3.0 s to T0+12.3 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -1.22 +/- 0.04 and the cutoff energy, parameterized as Epeak, is 473.00 +/- 82.60 keV The event fluence (10-1000 keV) in this time interval is (9.018 +/- 0.369)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0+0.58 s in the 10-1000 keV band is 13.31 +/- 0.37 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."