TITLE:   GCN CIRCULAR
NUMBER:  8150
SUBJECT: SGR 0501+4516: Decline in Activity
DATE:    08/08/28 01:10:37 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

This is a duplicate of ATEL #1683 (which should be cited instead of  
this GCN) copied to GCN as a courtesy to the gamma-ray burst community.

David Palmer (LANL) on behalf of the Swift Team, reports:

SGR 0501+4516 (ATEL #1675, #1676, #1677, #1678, #1682) has declined in  
activity. There have been no reported bursts in 43 hours, compared to  
the previous period with 56 bursts in 87 hours and a largest gap of 8  
hours.

Due to the unpredictable nature of these objects, this does not  
necessarily imply that it has returned to a multi-year (or even multi- 
day) quiescent stage.

As of the latest available Swift-BAT data, 2008-08-27 22:40 UT, the  
most recent reported burst from the SGR was detected by Konus-Wind on  
2008-08-26 at 03:16:15 (Konus-Wind team, private communication).  The  
most recent BAT detection was about 8 hours earlier.

The current list of BAT bursts, plus the reported Konus Wind bursts  
(from GCN #8132), follows.  As in ATEL #1676, which this expands, the  
bursts with more than 2000 counts in the BAT are marked with a '*'.


Trigger time (UTC) Trigger (ms) Notes

2008-08-22 12:41:59      64 *
2008-08-22 13:09:04     256
2008-08-22 13:12:53      16 *
2008-08-22 13:20:30           during slew
2008-08-22 14:17:55     256
2008-08-22 14:34:26      32
2008-08-22 17:29:30      64
2008-08-22 22:24:20      32
2008-08-22 22:36:53      32
2008-08-22 22:53:51      16
2008-08-23 00:28:13      32
2008-08-23 02:11:39         * during slew, 13k BAT counts
2008-08-23 04:47:49      16 * 35k BAT counts, seen by Konus-Wind
2008-08-23 06:31:37      16
2008-08-23 07:01:12           during slew, wrong time in ATEL #1678
2008-08-23 08:30:04      16 *
2008-08-23 08:34:57      32
2008-08-23 11:07:38      16
2008-08-23 11:27:35      16 * 90k BAT counts, seen by Konus-Wind
2008-08-23 14:27:37      64
2008-08-23 14:56:26      64 *
2008-08-23 16:31:22      16
2008-08-23 17:35:14      32 * 17k BAT counts
2008-08-23 17:35:15     128
2008-08-23 17:59:01       8
2008-08-23 19:08:10     128
2008-08-23 20:49:10     256
2008-08-23 20:53:29      16
2008-08-23 21:09:20      32
2008-08-23 21:11:17      64
2008-08-23 21:11:20      16
2008-08-23 21:13:40      64
2008-08-23 22:37:55       8
2008-08-24 00:05:30     128
2008-08-24 00:19:47       8 *
2008-08-24 01:17:55           Seen by Konus-Wind, not by BAT
2008-08-24 01:53:07      32
2008-08-24 02:02:47      32
2008-08-24 02:04:36      32
2008-08-24 06:56:53      32
2008-08-24 08:18:27      32
2008-08-24 08:23:39      16 * double peak
2008-08-24 08:23:39      32
2008-08-24 10:17:37     128
2008-08-24 18:19:38     128
2008-08-24 19:52:53      64 *
2008-08-24 22:30:12      16
2008-08-25 00:46:28      32
2008-08-25 03:19:18      32
2008-08-25 04:48:27           Seen by Konus-Wind, not by BAT
2008-08-25 10:22:03      16
2008-08-25 11:55:32      32
2008-08-25 19:24:09      32
2008-08-26 03:16:15           Seen by Konus-Wind, not by BAT

This GCN may not be cited.  Please cite ATEL #1683 instead.