GRB 070714
GCN Circular 6620
Subject
GRB 070714: Swift detection of a bright burst, possibly short
Date
2007-07-14T05:28:15Z (18 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>
J. L. Racusin (PSU), S. D. Barthelmy (GSFC), D. N. Burrows (PSU),
M. M. Chester (PSU), N. Gehrels (NASA/GSFC), H. A. Krimm (GSFC/USRA),
D. M. Palmer (LANL) and T. Sakamoto (NASA/ORAU) report on behalf of
the Swift Team:
At 04:59:29 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 070714 (trigger=284856). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 57.854, +28.295 which is
RA(J2000) = 03h 51m 25s
Dec(J2000) = +28d 17' 43"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve shows a duration of
3 seconds with a spike to a peak of 20000 counts/s (15-350 keV)
at T+0.2 s.
The XRT began observing the field at 05:00:30 UT, 61 seconds after the
BAT trigger. Using ground processed data, XRT found a bright, fading,
uncatalogued X-ray source located at RA, Dec 57.8423, +28.2978 which is
RA(J2000) = 03h 51m 22.1s
Dec(J2000) = 28d 17' 52.0"
with an uncertainty of 3.9 arcseconds (radius, 90% containment).
This location is 39 arcseconds from the BAT on-board position,
within the BAT error circle. The initial flux in the 2.5s image
was 2.4e-09 erg/cm2/s (0.2-10 keV).
The UVOT began observing the field at 05:00:40.05 UT, 70.4 s after the
BAT trigger. No counterpart is apparent in the 2.7' x 2.7' subimage,
based on visual comparison with the DSS. Additional processing is
underway.
Burst Advocate for this burst is J. L. Racusin (racusin AT astro.psu.edu).
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)
GCN Circular 6621
Subject
GRB 070714 : Liverpool Telescope optical counterpart ?
Date
2007-07-14T07:07:04Z (18 years ago)
From
Andrea Melandri at Liverpool John Moores U <axm@astro.livjm.ac.uk>
A. Melandri (Liverpool JMU) on behalf of the Liverpool GRB
team report:
On 2007 Jul 14 at 05:10:56 UT the 2-m Liverpool Telescope
automatically observed the field of GRB 070714 (trigger=284856,
Racusin et al. GCN 6620).
Due to the incoming dawn the automatic observation sequence stopped
after ~15 minutes, after the acquisition of only 9 frames.
Inside the XRT error circle (Racusin et al. GCN 6620) we find a
single source at the position (error of 0.5 arcsec)
RA = 03:51:22.2
Dec = +28:17:51.4
It is not a catalog source but presently it's not clear yet whether
the object is fading.
GCN Circular 6624
Subject
GRB 070714 ("Bastille"): Optical Pre-Imaging
Date
2007-07-14T22:47:19Z (18 years ago)
From
Josh Bloom at UC Berkeley <jbloom@astron.berkeley.edu>
P. Nugent (LBL) and J. S. Bloom (UC Berkeley) report:
We have created a stacked image through the co-addition of 8
unfiltered images taken by the NEAT collaboration and 51 images in
the RG610 filter taken by the Palomar-Quest Consortium at the Palomar
Oschin Schmidt telescope (obtained from 2002-2006), of what is being
called a short-hard burst (SHB) 070714A (Barbier et al.; GCN #6622).
The stacked image is significantly deeper than the DSS (3 sigma limit
of R~22.7 mag). There is no source at the position of the proposed
counterpart (Melandri et al. GCN #6621). Since this Liverpool
Telescope source was detected in twilight, it was likely seen near
the DSS limit (or brighter) and thus, while we cannot say for sure
(since no magnitude was given in GCN #6621), the absence of a
similarly bright source in our image suggests that the Melandri et
al. source was indeed the afterglow.
Note that the source @ position RA = 03:51:21.24, DEC = +28:17:45.5
is in the 2MASS catalog and is blue (J - K = 0.5 mag).
This message may be cited.