GCN Circular 4936
Subject
SGR 1900+14: bright burst detected by Konus-Wind on March 28
Date
2006-03-29T15:48:50Z (20 years ago)
From
Valentin Pal'shin at Ioffe Inst <val@mail.ioffe.ru>
S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, and
T. Cline on behalf of the Konus-Wind team report:
A bright SGR-like burst 060328 was detected by Konus-Wind
at 32580.175 s UT (09:03:00.175).
The Konus-Wind ecliptic latitude response is consistent with SGR 1900+14
position (and is inconsistent with the positions of all other known SGRs).
So, taking in account the resuming SGR 1900+14 activity detected
recently by Swift-BAT (Vetere et al., GCN 4922; Sato et al., GCN 4923,
4924), we believe that this burst originated from this SGR.
The recent Swift-BAT reports on detections of SGR 1900+14 bursts on
March 29 (Moretti et al., GCN 4933; Romano et al., GCN 4934) also
confirm our conclusion.
At the time of the burst Swift was in SAA.
The burst light curve shows the main two-peaked pulse with a duration of
~0.13 sec and a much weaker precursor at T-T0~ -0.14 with a duration of
~0.03 sec.
The burst had a fluence 1.06(-0.10,+0.08)x10^-6 erg/cm2, and
a peak flux measured from T0+0.026 sec on 4 msec time scale
2.18(-0.35,+0.33)x10^-5 erg/cm2/sec
(both in the 20-200 keV energy range).
The spectrum integrated over the most intense part of the burst (from
T-T0=0 to T-T0=0.064 sec) is well fitted (in the 20-200 keV range)
by the OTTB spectral model:
dN/dE ~ E^{-1} exp(-E/kT),
with kT = 21.6 +/ 2.0 keV.
All the quoted errors are at the 90% confidence level.