GRB 070103
GCN Circular 5988
Subject
GRB 070103: Swift detection of a burst
Date
2007-01-03T21:12:06Z (18 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>
T. Sakamoto (NASA/ORAU), S. D. Barthelmy (GSFC), D. N. Burrows (PSU),
M. M. Chester (PSU), J. R. Cummings (NASA/UMBC),
N. Gehrels (NASA/GSFC), S. T. Holland (CRESST/GSFC/USRA),
S. Immler (GSFC/USRA), J. A. Kennea (PSU), H. A. Krimm (GSFC/USRA),
V. Mangano (INAF-IASFPA), F. E. Marshall (NASA/GSFC),
K. M. McLean (LANL/UTD), C. Pagani (PSU), S. B. Pandey (UCL-MSSL),
A. M. Parsons (GSFC), P. Romano (Univ. Bicocca & INAF-OAB),
B. Sbarufatti (INAF-IASFPA), D. E. Vanden Berk (PSU) and
H. Ziaeepour (UCL-MSSL) report on behalf of the Swift Team:
At 20:46:39.41 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB (trigger=254532). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA=352.557, Dec=+26.875 (J2000), which is
RA(J2000) = 23h 30m 14s
Dec(J2000) = +26d 52' 32"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve shows two peaks separated
by ~10 sec and a few more weak peaks extending out to ~T+20 sec.
The peak count rate was ~2400 counts/sec (15-350 keV), at ~0 sec
after the trigger.
The XRT began taking data at 20:47:48 UT, 69 seconds after the BAT
trigger. The XRT on-board centroid algorithm did not find a source in the
image, however analysis of downlinked data reveals an uncatalogued point source
at the position RA=352.5576, Dec=+26.8751 (J2000), which is
RA(J2000) = 23h 30m 13.82s
Dec(J2000) = +26d 52' 30".21
with 4.74 arcsec error radius (90% containment).
UVOT took a finding chart exposure of 100 seconds with the White
(160-650 nm) filter starting 74 seconds after the BAT trigger, and a
400 second exposure with the V filter starting 179 seconds after the
trigger. No afterglow candidate has been found in the initial data
products. The 2.7'x2.7' sub-image covers 100% of the XRT error
circle. The 3-sigma upper limit is 19.5 in white, 18.8 in V. No
correction has been made for the expected extinction corresponding to
E(B-V) of 0.07.
GCN Circular 5989
Subject
GRB 070103: TAROT Calern observatory optical observations
Date
2007-01-03T21:16:26Z (18 years ago)
From
Alain Klotz at CESR-CNRS <Alain.Klotz@free.fr>
Klotz, A. (CESR-OMP), Boer M. (OHP), Atteia J.L. (LATT-OMP) report:
We imaged the field of GRB 070103 detected by SWIFT
(trigger 254532) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.
The observations started 23.3s after the GRB trigger
(8.4s after the notice). The elevation of the field decreased from
from 32 degrees above horizon and weather conditions
were good.
The date of trigger : t0 = 2007-01-03T20:46:39.072
The first image is trailed with a duration of 60.0s
(see the description in Klotz et al., 2006, A&A 451, L39).
We do not detect any OT with a limiting magnitude of:
t0+23.3s to t0+83.3s : R > 15.1
The second image is 30.0s exposure in tracking mode:
t0+89.7s to t0+119.7s : R > 15.9
We co-added a series of exposures:
t0+89.7s to t0+229.0s : R > 16.4
Magnitudes were estimated with the nearby USNO-B1 stars
and are not corrected for galactic dust extinction.
N.B. Galactic coordinates are lon=101.3840 lat=-32.5757
and the galactic extinction in R band is 0.1 magnitude
estimated from D. Schlegel et al. 1998ApJ...500..525S.
This message may be cited.
GCN Circular 5990
Subject
GRB 070103: NOT observations
Date
2007-01-03T23:37:33Z (18 years ago)
From
Daniele Malesani at Niels Bohr Inst,Dark Cosmology Center <malesani@astro.ku.dk>
D. Malesani (NBI-DARK), E. Stempels (Univ. St. Andrews), J.P.U. Fynbo,
J. Hjorth (NBI-DARK), report:
We observed the field of GRB 070103 (Sakamoto et al., GCN 5988) with the
NOT equipped with the ALFOSC camera. Weather conditions were not optimal
with passing clouds.
We do not detect any source at the position of the X-ray afterglow, down
to limiting magnitudes R ~ 21.2 and I ~ 21, calibrated using
instrumental zeropoints. Mid times of the exposures were Jan 3.886 (R)
and Jan 3.901 UT (I), that is 37 and 50 minutes after the GRB, respectively.
We encourage observations at longer wavelengths.
GCN Circular 5991
Subject
GRB 070103, Swift-BAT refined analysis
Date
2007-01-03T23:56:53Z (18 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>
L. Barbier (GSFC), S. D. Barthelmy (GSFC), J. Cummings (GSFC/UMBC),
E. Fenimore (LANL), N. Gehrels (GSFC), 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)
on behalf of the Swift-BAT team:
Using the data set from T-110 to T+303 sec from the recent telemetry
downlink, we report further analysis of BAT GRB 070103 (trigger #254532)
(Sakamoto, et al., GCN Circ. 5988). The BAT ground-calculated position
is RA, Dec = 352.582, 26.823 deg, which is
RA(J2000) = 23h 30m 19.6s
Dec(J2000) = 26d 49' 22.1"
with an uncertainty of 2.6 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 84%.
The mask-weighted lightcurve has three main peaks at T+0, 10 and 18 sec.
T90 (15-350 keV) is 19 +- 1 sec (estimated error including systematics).
The time-averaged spectrum from T-0.1 to T+21.6 is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
2.0 +- 0.2. The fluence in the 15-150 keV band is 3.4 +- 0.5 x 10^-7
erg/cm2. The 1-sec peak photon flux measured from T-0.11 sec in the
15-150 keV band is 1.1 +- 0.1 ph/cm2/sec. All the quoted errors are
at the 90% confidence level.
GCN Circular 5992
Subject
GRB070103: Swift XRT refined analysis
Date
2007-01-04T10:42:35Z (18 years ago)
From
Vanessa Mangano at INAF-IASFPA <vanessa@ifc.inaf.it>
Vanessa Mangano, Boris Sbarufatti, Teresa Mineo (INAF-IASFPA)
report on behalf of the Swift XRT team:
We analysed the first seven orbits of XRT data of GRB070103
(Sakamoto et al., GCN 5988) consisting of 12 ks of exposure
in Photon Counting (PC) mode in the time interval form 100 s
to 30 ks from the trigger.
The refined position of the source is
RA (2000) = 23h 30m 13.90s
Dec (2000) = +26d 52' 34.17"
with an uncertainty of 3.7 arcsec (90% containment).
This is 4.1 arcsec from the preliminary XRT position and
3.44 arcmin form the refined BAT position
(Barbier et al., GCN 5991).
The 0.3-10 keV X-ray light curve shows an initial flare
peaking at about 500 s from the trigger, followed (after
the first orbital gap) by a power law decay with slope
-1.4 +/- 0.1 up to 30 ks.
If decaying at the present rate the source will reach
a count rate level of 1.5e-3 counts/s
(corresponding to flux level of 1.e-13 erg cm^-2 s^-1)
at T+24 hr.
The PC spectrum is well fit by an absorbed power law
with photon index 2.3 +/- 0.1 and N_H (3.2 +/- 0.7) e21 cm^-2
in excess with respect to the Galactic value of 5.0e20 cm^-2.
The average 0.3-10 keV unabsorbed flux during the observation
is 3.8e-12 erg cm^-2 s^-1.
This circular is an official product of the Swift XRT team.
GCN Circular 5993
Subject
GRB 070103: Swift/UVOT Upper limits
Date
2007-01-04T15:42:47Z (18 years ago)
From
Stephen Holland at USRA/NASA/GSFC/SSC <sholland@milkyway.gsfc.nasa.gov>
S. T. Holland (CRESST/GSFC/USRA) and T. Sakamoto (NASA/ORAU)
report on the behalf of the Swift UVOT team:
The Swift/UVOT observed the field of GRB 070103 starting 55 s
after the BAT trigger (Sakamoto et al. 2007, GCN Circ. 5988). We do
not find any source, in any of the UVOT observations, inside the
refined XRT error circle (Mangano et al., 2007 GCN Circ. 5992).
The 3-sigma upper limits for detecting a source anywhere inside
the XRT error circle in the V-band settling image, the finding-chart
exposures, and the co-added frames are:
Filter T_start T_stop Exp(s) Mag (3-sigma upper limit)
-----------------------------------------------------------------
V settling 55 65 9 16.5
V finding 180 580 393 19.6
V finding 857 1257 393 19.6
White finding 75 175 98 19.8
V 55 23,730 2881 20.8
B 5652 30,281 1235 21.3
U 634 36,065 3344 21.6
UVW1 610 35,291 3778 21.5
UVM2 586 34,384 2930 21.4
UVW2 686 22,816 1318 21.0
White 75 6056 411 20.7
-----------------------------------------------------------------
The values quoted above are not corrected for the expected Galactic
extinction corresponding to a reddening of E_{B-V} = 0.07 mag towards
the direction of the burst (Schlegel et al. 1998).
GCN Circular 5994
Subject
GRB070103: KPNO 4m+FLAMINGOS J limit
Date
2007-01-04T19:39:46Z (18 years ago)
From
Adria C. Updike at Clemson U <aupdike@clemson.edu>
A. C. Updike, D. H. Hartmann (Clemson University), S. Klose (TLS), and A. Fruchter (STScI) report on behalf of a larger collaboration:
GRB 070103 (GCN 5988, T. Sakamoto et al.) was observed using the KPNO 4m + FLAMINGOS. Observations in the J band began at UT 01:40:53 (4 hours and 54 minutes after the burst). We obtained 13 x 5 min exposures. At the refined XRT position (GCN 5992, V. Mangano et al.) we detect no new sources in the stacked image brighter than J=21 magnitudes calibrated with respect to the 2MASS point source catalog. This limit is based on the faintest sources detected using Sextrator with a 1 sigma uncertainty of 0.2 magnitudes.
The Clemson University GRB Response Site may be found at:
http://people.clemson.edu/~kgarime/burst/index.php
We would like to acknowledge the excellent support of NOAO staff and observers, particularly E. Lada, N. Rashkind, M. Huerta, H. Halbedel, D. Joyce, K. M. Merrill, and B. Jannuzi.
These observations were carried out under the NOAO-Clemson GRB ToO program 2006B-0594.
This message may be cited.
GCN Circular 5996
Subject
GRB070103: APO SPIcam i' and z' limits
Date
2007-01-05T02:09:44Z (18 years ago)
From
Hsiao-Wen Chen at U Chicago <hchen@oddjob.uchicago.edu>
H.-W. Chen (U Chicago), J. Dembicky (APO), D. York, D. Lamb (U Chicago),
R. McMillan, B. Ketzeback, and G. Saurage (APO) report on behalf of a
larger collaboration:
"We obtained 5x600 sec dithered exposures in each of the SDSS i' and
z' bands of the field of GRB070103 (Sakamoto et al., GCN 5988), using
the SPIcam on the 3.5 m telescope at the Apache Point Observatory. The
observations started at Jan 04.05 UT (~ 4.5 hrs after the initial
Swift trigger) under photometric conditions with a mean seeing of 1.6-2
arcsec. Calibrating the final stacks based on a SDSS standard field
observed through these filters gives 5-sigma depths of AB(i')=24.6 and
AB(z')=24.0 over a 2-arcsec diameter aperture at the location of the
x-ray source reported by Mangano et al. (GCN 5992). "