GCN Circular 21100
E. Bissaldi (Politecnico & INFN Bari), V. Connaughton (USRA) and O.J. Roberts (USRA/NASA) report on behalf of the Fermi GBM Team: "At 07:51:32.38 UT on 16 May 2017, the Fermi Gamma-Ray Burst Monitor triggered on a burst from AXP CXOU J164710.2-455216 (trigger 516613897 / 170516327), which was detected by the Swift/BAT and Swift/XRT approximately 42 min earlier than the GBM trigger (D'Ai et al. 2017, GCN 21095). The GBM on-ground location is consistent with the known position of the source. The angle from the Fermi-LAT boresight at the GBM trigger time is 79 degrees. The GBM light curve shows a single peak with a duration of about 0.1 s. The time-averaged spectrum from T0-64 ms to T0+80 ms is adequately fit by a blackbody model with kT = 6.6 +/- 0.4 keV. The event fluence (8-100 keV) in this time interval is (6.46 +/- 0.05)E-08 erg/cm^2. The photon flux (8-100 keV) is 12.6 +/- 0.9 ph/s/cm^2. The spectral analysis results presented above are preliminary. These events are sometimes bright enough that some are being classified by the flight software as GRBs. We will correct this classification in the online catalogue at the Fermi Science Support Center: http://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigtrig.html but will not issue further circulars to correct the classification."