Skip to main content
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 3613

Swift detection of a long transient (GRB 050714B?)
2005-07-15T00:25:37Z (19 years ago)
Andrew Levan at U.of Leicester <>
A. Levan, A. Beardmore, K. Page, J. Osborne, E. Rol (U. Leicester)
S. Barthelmy, J. Cannizzo (GSFC-UMBC), L. Cominsky (Sonoma State U.),
H. Krimm (GSFC), C. Markwardt (GSFC/UMD), D. Palmer (LANL), T. Sakamoto
(GSFC), C. Gronwall, D. Burrows, P. Roming, J. Kennea (PSU) and N. Gehrels
(GSFC) report for the Swift team.

At 22:40:32 UT, Swift-BAT triggered (trigger=145994) and located on-board
a source.  The flight-determined location is RA,Dec 169.694, -15.528 {+11h
18m 47s, -15d 31' 39"} (J2000) with an uncertainty of 3 arcmin (radius,
90% containment, stat+sys). The spacecraft was on target at approximately
150 seconds.  This was a very weak 64-sec image-trigger detection right at
the image-trigger threshold (10.1 sigma). There are no "peaks" in the BAT
lightcurve, which is consistent with a long low-amplitude event, and that
it was an image trigger and not a rate trigger. At this early stage in the
analysis, we can not distinguish between a long GRB and a hard X-ray
transient.  However, we do think that it is from a real astrophysical

The spacecraft slewed immediately and the XRT began observing the burst
at 22:43:00.6 UT (151 s after the BAT trigger).  XRT found a
bright, uncatalogued, fading X-ray source. The position, calculated with
xrtcentroid on the TDRSS postage stamp image, is:

RA:     11h 18m 47.9s (J2000),
Dec:   -15d 32' 55.5" (J2000).

This position is 76.5 arcseconds from the BAT position.  The estimated
uncertainty is 6 arcseconds radius (90% containment).

The Swift Ultra Violet/Optical Telescope (UVOT) observations began at
22:43:03 UT, 151 seconds after the BAT trigger. The first data taken after
the spacecraft settled was a 100 seconds exposure using the V filter with
the midpoint of the observation at 201 seconds after the BAT trigger.
There is no new source at the XRT position.
Looking for U.S. government information and services? Visit