GRB 070612B
GCN Circular 6511
Subject
GRB 070612B: Swift detection of a burst
Date
2007-06-12T06:33:33Z (18 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>
D. Grupe (PSU), S. D. Barthelmy (GSFC), P. A. Evans (U Leicester),
N. Gehrels (NASA/GSFC), S. T. Holland (CRESST/GSFC/USRA),
J. A. Kennea (PSU), W. B. Landsman (NASA/GSFC),
C. B. Markwardt (CRESST/GSFC/UMD), D. M. Palmer (LANL),
J. L. Racusin (PSU), P. Romano (Univ. Bicocca & INAF-OAB) and
M. C. Stroh (PSU) report on behalf of the Swift Team:
At 06:21:17 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 070612B (trigger=282073).
The BAT on-board calculated location is
RA, Dec 261.713, -8.719 which is
RA(J2000) = 17h 26m 51s
Dec(J2000) = -08d 43' 06"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve showes a single peak
with a duration of about 20 sec. The peak count rate
was ~2000 counts/sec (15-350 keV), at ~0 sec after the trigger.
Because of an Earth limb constraint, the spacecraft did not slew promptly
to the BAT position, and so there are no immediate XRT or UVOT data
products to analyze. XRT and UVOT will begin observing this target
at 07:13 UT.
GCN Circular 6514
Subject
GRB 070612B: Swift XRT position from downlink data
Date
2007-06-12T07:49:35Z (18 years ago)
From
Dirk Grupe at PSU/Swift-XRT <grupe@astro.psu.edu>
D. Grupe (PSU), P. Evans (U Leicester), report on behalf of the Swift Team:
Swift XRT started observing the afterglow of GRB 070612B (GCN circ 6511)
at 07:15:15.59, 3239s after the BAT trigger. We found a bright,
uncatalogued, possibly fading source in the XRT data.
Using 272 of prompt downlinked data, we find a position RA, Dec
261.7267, -8.7524 which is
RA(J2000) = 17 26 54.4
Dec(J2000) = -08 45 08.7
with an uncertainty of 4.7 arcsec (radius, 90% containment).
Further analysis of the data will be performed with the ground-processed
data.
GCN Circular 6516
Subject
GRB 070612B: KAIT limits
Date
2007-06-12T08:32:16Z (18 years ago)
From
Weidong Li at UC Berkeley KAIT/LOSS <weidong@astron.berkeley.edu>
W. Li, R. J. Foley, D. A. Perley, J. S. Bloom, and A. V. Filippenko,
University of California, Berkeley, on behalf of the KAIT GRB team, report:
The robotic 0.76-m Katzman Automatic Imaging Telescope (KAIT)
at Lick Observatory observed GRB 070612B detected with Swift
(Trigger 282073; Grupe et al. GCN 6511). The automatic sequence
started at 06:22:01, 44 s after the burst. The BAT location
and the XRT position (Grupe & Evans GCN 6514) have been monitored
in V, I, and clear filters, with varying exposure times. The observations
are still on-going. Our image processing pipeline did not find any
new objects within the XRT error circle, with the following photometry
limits (calibrated with USNO B1.0). These magnitudes have not been
corrected for Galactic extinction, which as estimated by the NED
extinction calculator is approximately E(B-V) = 0.838 mag in this
direction.
======================================================================
Start UT t(GRB) Filter Exp(s) 3sigma-limit
06:22:01 44s clear 5.0 18.1
06:22:09 52s clear 5.0 18.2
06:22:17 60s clear 5.0 18.2
06:22:25 68s clear 5.0 18.1
06:22:34 77s clear 5.0 18.1
06:22:42 85s clear 5.0 18.1
06:23:10 113s V 15.0 17.1
06:23:36 139s I 15.0 18.0
06:24:00 163s clear 15.0 18.8
06:24:31 194s V 45.0 17.6
06:25:27 250s I 45.0 18.5
06:26:21 304 clear 45.0 19.3
========================================================================
More images, mostly 60 s exposures in the I and clear filters,
have been obtained. No obvious OA was found in the XRT error
circle to a limiting magnitude of 19.0 - 19.9 mag, at
t= 304s to 6642s after the burst.
More analyses are in progress.
GCN Circular 6517
Subject
GRB070612B: P60 Observations
Date
2007-06-12T08:56:35Z (18 years ago)
From
S. Bradley Cenko at Caltech <cenko@srl.caltech.edu>
S. B. Cenko, A. Rau (Caltech) and D. B. Fox (Penn State) report on behalf
of a larger collaboration:
We have imaged the field of GRB070612B (Grupe et al., GCN 6511) with the
automated Palomar 60-inch telescope. Images were taken in the Kron R and
Sloan i' and z' filters beginning approximately 12 minutes after the
burst.
We find no sources inside the XRT error circle (Grupe and Evans, GCN
6514). Photometric calibration for the limits below was performed using
USNO B-1 mangitudes converted to the SDSS photometric sytem using
empirical relations from Jordi, Grebel & Ammon (A&A 460, 339, 2006):
t_b (min.) Filter Mag. Limit
-----------------------------------------------------------------------
21.2 i' > 21.0
22.7 z' > 20.5
We marginally detect a source just outside of the XRT error circle in our
i' coaddition. The source, with i' magnitude ~ 22.0, is located at
coordinates (J2000.0):
RA: 17:26:54.936
Dec: -08:45:08.35
This source is not present in either our R- our z'-band imaging of
this field. Because of the faintness, we cannot assess the variability
of this source at the present time.
GCN Circular 6518
Subject
GRB 070612B: FRAM limit
Date
2007-06-12T13:16:52Z (18 years ago)
Edited On
2024-11-18T10:09:44Z (7 months ago)
From
Martin Jelinek at Inst.Astrophys.Andalucia,Granada <mates@iaa.es>
Edited By
Judith Racusin at NASA/GSFC <judith.racusin@nasa.gov> on behalf of Leo P. Singer at NASA/GSFC <leo.p.singer@nasa.gov>
Martin Jelínek, Petr Kubánek (IAA CSIC Granada, Spain),
and Michael Prouza (Columbia U. New York, USA and FZU Praha, Czech Rep.)
on behalf of the FRAM team, coordinated by FZU Praha, Czech Rep.
report
"The wide field camera of the telescope FRAM, located
at Pierre Auger observatory in Malargue, Argentina,
followed the Swift GRB 070612B (Grupe et al. GCNs
6511 and 6514).
20s R-band (lambda_eff = 640nm, limmag = 14.8) images
were obtained starting 62s after the GRB (45s after
receiving the notification).
We do not detect any new source in single nor combined
images within the BAT or XRT errorboxes."
this message may be cited
GCN Circular 6519
Subject
GRB 070612B: Swift/UVOT upper limits
Date
2007-06-12T15:15:50Z (18 years ago)
From
Wayne Landsman at GSFC/SSAI <landsman@milkyway.gsfc.nasa.gov>
W. Landsman (NASA/GSFC) and D. Grupe (PSU) report on behalf of the
Swift/UVOT team.
The Swift/UVOT observed the field of GRB 070612B starting 3256 s after
the BAT trigger (Grupe et al., GCN Circ. 6511). The UVOT observations
were delayed due to a Earth-limb constraint.
We do not find any source in any of the UVOT observations inside the
refined XRT error circle (Grupe et al., GCN Circ. 6514). The 3-sigma
upper limits for detecting a source in the first finding chart (FC)
exposure and co-added frames are:
Filter T_start(s) T_stop(s) Exp(s) Mag (3-sigma UL)
Wh (FC) 3256 3356 98 >20.3
Wh 3256 9882 1201 >21.7
V 3238 11624 1113 >20.0
B 4180 5813 393 >20.4
U 3975 5608 393 >20.1
UVW1 3772 5404 393 >20.1
UVM2 3567 5199 393 >20.0
UVW2 4590 10888 1082 >20.9
GCN Circular 6521
Subject
GRB 070612B: Swift-XRT refined analysis
Date
2007-06-12T20:01:19Z (18 years ago)
From
Dirk Grupe at PSU/Swift-XRT <grupe@astro.psu.edu>
D. Grupe (PSU) reports on behalf of the Swift/XRT team
We have analyzed two orbits of GRB 070612B (Grupe et al., GCN 6509)
with total observing times of 4.7 ks
in Photon Counting mode in the Swift XRT.
Due to Earth-constrain Swift did not slew immediately and XRT
observations were
delayed by almost one hour (Grupe \& Evans, GCN 6514).
The Photon Counting mode image
provides a refined XRT position at
Ra, Dec= 261.7271, -8.7517, which is
RA(J2000) = 17h 26m 54.49s
Dec(J2000) = -08d 45' 06.3"
with an error of 4.0" (90% confidence). This position is 2.7 "
away from the preliminary XRT position reported in GCN 6514.
The X-ray light curve shows a decaying source. While the afterglow is
clearly
detected in the first orbit, only a 3sigma upper limit of 0.012 counts/s
can be
given for the second orbit.
Based on this result, we estimated a decay slope of 2.8+/-0.6.
The X-ray data can be fitted by a single power law with a photon
index Gamma=1.7+-0.8 and the absorption column density fixed to the Galactic
value of NH=1.68e21
cm-2 (Dickey & Lockman, 1990) with chi2/dof=4/3.
This circular is an official product of the Swift XRT team.
GCN Circular 6523
Subject
GRB 070612B, Swift-BAT refined analysis
Date
2007-06-12T20:39:42Z (18 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>
J. Cummings (GSFC/UMBC), L. Barbier (GSFC), S. D. Barthelmy (GSFC),
E. Fenimore (LANL), N. Gehrels (GSFC), D. Grupe (PSU),
H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), D. Palmer (LANL),
A. Parsons (GSFC), T. Sakamoto (GSFC/ORAU), G. Sato (GSFC/ISAS),
M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. Ukwatta (GWU)
(i.e. the Swift-BAT team):
Using the data set from T-240 to T+962 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 070612B (trigger #282073)
(Grupe, et al., GCN Circ. 6511). The BAT ground-calculated position is
RA, Dec = 261.716, -8.747 deg which is
RA(J2000) = 17h 26m 51.8s
Dec(J2000) = -8d 44' 48"
with an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 17%.
The mask-weighted light curve shows a single roughly symetrical peak
starting at T-5 sec, peaking at T+0 sec, and ending at T+12 sec.
T90 (15-350 keV) is 13.5 +- 1 sec (estimated error including systematics).
The time-averaged spectrum from T-6.4 to T+10.3 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.55 +- 0.11. The fluence in the 15-150 keV band is 1.7 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T-0.16 sec in the 15-150 keV band
is 2.6 +- 0.4 ph/cm2/sec. All the quoted errors are at the 90% confidence
level.
GCN Circular 6524
Subject
GRB 070612B: SARA upper limit
Date
2007-06-12T21:22:00Z (18 years ago)
From
Adria C. Updike at Clemson U <aupdike@clemson.edu>
Adria C. Updike, Dieter H. Hartmann (Clemson University), Gary Henson
(ETSU), Robert Mesler, Christina Bunker, and Jason Carson (ETSU/SARA REU
program) report:
Using the 0.9m SARA telescope at Kitt Peak, we imaged the field of GRB
070612B (GCN 6511, Grupe et al.). Observations began 24 minutes after
the trigger (282073) and consisted of 65 minutes of R-band images.
We do not detect any new sources in the refined XRT error box (GCN 6521,
Grupe et al.) or at the position indicated by P60 (GCN 6517, Cenko et
al.) down to a limiting magnitude of 20.6 +/- 0.6 in the R-band as
calibrated relative to 10 USNO B1.0 stars.
The SARA Homepage can be found at:
http://saraobservatory.org
This message may be cited.
GCN Circular 6541
Subject
GRB 070612B: optical observations
Date
2007-06-16T09:01:57Z (18 years ago)
From
Giuseppe Greco at U Bologna <giuseppe.greco2@studio.unibo.it>
G. Greco (Bologna University), F. Terra (Second University of
Roma "Tor Vergata"), C. Bartolini, A. Guarnieri, A. Piccioni
(Bologna University), G. Pizzichini (INAF/IASF Bologna),
D. Nanni (INAF/OAR and Second University of Rome "Tor Vergata"),
R. Gualandi (Bologna Observatory) report:
We imaged the field of GRB 070612B (Grupe et al., GCN 6511) with the
152 cm Loiano telescope in the Rc and Ic filters in clear sky conditions.
We do not detect any new sources in the combined images within the
XRT error box (Grupe and Evans, GCN6521) with the following upper limits:
tmid (UT) filter Exp. Limit
June 13.917 Rc 3x1800 22.2 (3 sigma)
June 13.975 Ic 3x1200 22.0 (3 sigma)
We detect the faint source indicated by Cenko et
al. (GCN 6521) at an Ic-band magnitude of 21.9+/-0.16
Magnitude and upper limits were estimated by comparison with the
USNO-B1 stars and are not corrected for galactic dust extinction.
The co-added Ic image, in which the comparison stars are marked, has been
posted in our public directory from where it can be retrieved
by sftp using
hostname: ermione.bo.astro.it
username: publicGRB
password: GRB_bo.
directory: GRB070612B
[GCN OPS NOTE(17jun07): Per author's request, the reference to "GCN 6517"
was corrected to "GCN 6521", and "GCN6514" was corrected to "GCN 6521".]
GCN Circular 6553
Subject
GRB 070612B: Optical Observation by MITSuME Akeno
Date
2007-06-18T06:36:27Z (18 years ago)
From
Nobuyuki Kawai at Tokyo Tech <nkawai@hp.phys.titech.ac.jp>
Y.kudo, T. Ishimura, Y. Yatsu, T. Shimokawabe, N. Vasquez, and
N. Kawai (TokyoTech) report on behalf of the MITSuME collaboration:
We observed the error box of GRB070612B (Grupe et al., GCN 6511)
with the 3-color 50cm MITSuME Telescope at Akeno, Japan starting at
11:46:53 June 12 UT, 5.1 hours after the trigger.
In the co-added images of Ic, Rc, and g' bands, we did not detect
any new source in the XRT error circle. The 3-sigma limiting
magnitudes based on USNO-B1.0 (I-band) and NOMAD (R-band,g'-band)
stars are following.
Filter start time end time Exp(s) Mag (3-sigma upper limit)
-----------------------------------------------------------------
g' 11:46:53 12:16:35 25 x 60s 17.4
Rc 11:46:53 12:16:35 25 x 60s 18.6
Ic 11:46:53 12:16:35 25 x 60s 18.6
-----------------------------------------------------------------