[vsnet-grb-info 6717] Swift-BAT refined analysis of AXP 1E1547.0-5408 (Trigger 330353)

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  8318
SUBJECT: Swift-BAT refined analysis of AXP 1E1547.0-5408 (Trigger 330353)
DATE:    08/10/03 23:29:59 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott at lheamail.gsfc.nasa.gov>

H. A. Krimm (GSFC/USRA), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),
C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC),
G. Sato (ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC),
T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-239 to T+829 sec from recent telemetry downlinks,
we report further analysis of BAT trigger 330353 (Krimm, et al.,
GCN Circ. 8312).   We are not quoting the usual refined ground position
at this time because the automated processing did not choose an optimum
time interval for the position analysis.  Howver, it is consistant
with the catalog position of the 1E1547.0-5408 source.
The partial coding was 95%.
 
The mask-weighted light curve shows a spike with a duration of about 64 msec
at the time of the trigger.  There were multiple spikes from this source:
a smaller one at T-2.45 sec, slightly larger ones at ~T+105 and ~T+290 sec,
and much larger ones at ~T+420 and ~T+520 sec.
 
The time-averaged spectrum from T-0.016 to T+0.080 sec is best fit by a power law
with an exponential cutoff.  This fit gives a photon index -0.11 +- 0.79,
and Epeak of 21.9 +- 9.5 keV (chi squared 43.1 for 49 d.o.f.).
A simple power law fit yields and index 1.81 +- 0.15.