GCN Circular 8857
Subject
AXP 1E1547.0-5408: RHESSI observations up to 400 keV
Date
2009-01-28T01:40:47Z (15 years ago)
From
Eric Bellm at UCB/SSL <ebellm@ssl.berkeley.edu>
E. Bellm, D. M. Smith, and K. Hurley on behalf of the RHESSI team report:
On January 22, 2009, RHESSI observed repeated outbursts from AXP
1E1547.0-5408 (Gronwall et al., GCN 8833). After a single ~2 second burst
at 03:50:38 UT, a series of bursts was recorded from 05:14:03--05:26:51
UT. A second series was observed from 06:43:48--06:55:57 UT. The periods
without observed emission are attributable to SAA passages and Earth
occultation.
The brightest burst was observed at 06:48:05 UT. This burst showed an
initial spike with a peak count rate of 2.6E5 counts/s over a 10 ms
interval and emission to 400 keV. The spike was followed by the pulsing
tail (~2 s period) reported by Mereghetti et al. (GCN 8841) using INTEGRAL
SPI-ACS. A previous burst at 06:45:13.54 UT may have been brighter, as
its peak showed evidence of saturation. A one minute complex of bursts
beginning at 05:17:40 UT showed emission to 250 keV.
RHESSI observed a fast spike from the SGR at 05:18:32.45 UT. This event
had an initial peak with a background-to-peak rise time of 12 ms and FWHM
of 16 ms. A shoulder after the initial peak extended the total duration
(T90) to 70 ms. This spike was also observed by INTEGRAL SPI-ACS. A
lightcurve for this burst is available at
http://ssl.berkeley.edu/ipn3/1E1547/rhessi.pdf
[GCN OPS NOTE(29jan09): Per author's request, the missing "7" was added
to the URL.]