Andrew C Collazzi (NASA/ORAU), George Younes (NASA/USRA) and
Chryssa Kouveliotou (NASA/MSFC) report on behalf of the
Fermi GBM-Magnetar Team.
"At 02:11:29.43 UT on 7 May, 2013, the Fermi Gamma-ray Burst
Monitor (GBM) triggered and located an SGR-like burst (trigger
389585492 / 130507.091). The on-ground calculated location, using
the Fermi GBM trigger data, is RA = 281.22, Dec = -2.12 (J2000
degrees, equivalent to J2000 18h 45m, -2d 7'), with a statistical
uncertainty of 8.9 degrees (radius, 1-sigma containment, statistical
only; there is additionally a systematic error which is currently
estimated to be 2 to 3 degrees).
The 3-sigma error region for the burst contains several known
magnetars, but does not include the recently discovered magnetar
at the galactic center, SGR J1745-29 (Atel #5020).
The burst consists of a single pulse with a duration of
T90 = 20 +/- 9 ms.
The burst spectrum is adequately fit by a single blackbody with a
kT = 9.8 +/- 0.7 keV. The corresponding peak flux integrated over
4ms (8-200 keV) is (2.2 +/- 0.4)E-06 erg/s/cm^2. The fluence during
T0-0.020s to T0+0.016s is (3.8 +/- 0.4)E-8 erg/cm^2.
The analysis results presented above are preliminary."