GRB 120729A
GCN Circular 18184
Subject
GRB 120729A: KAIT Optical Observations
Date
2015-08-20T18:56:44Z (10 years ago)
From
Xiang-Gao Wang at GuangXi U <wangxg@gxu.edu.cn>
Xianggao Wang (UC Berkeley, GXU, UNLV), WeiKang Zheng,
Alexei V. Filippenko (UC Berkeley), and S. Bradley Cenko
(GSFC) report on behalf of the KAIT GRB team:
The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at
Lick Observatory, responded to Swift GRB 120729A (Ukwatta et al.,
GCN 13530) starting at 10:58:16 UT, 122 s after the burst.
Observations were performed with an automatic sequence in the
clear (roughly R), V, and I filters, and the exposure time was
20 s per image. The bright optical afterglow (Ukwatta et al. GCN 13530,
Virgili et al. GCN 13531, Oates et al. GCN 13539, Im et al. 13544,
Wren et al. 13545, Khamitov et al. GCN 13548, Gorosabel GCN 13550,
D'Avanzo et al. GCN 13551, Smith et al. GCN 13554) was detected
in all three filters. Useful observations lasted for about 2.4 hours.
Preliminary analysis shows that the afterglow decays with a single
power (with alpha = -0.87) beyond 1000 s after the burst. A light
curve is posted at
http://astro.berkeley.edu/~zwk/grb/GRB120729A/GRB120729A_kait.png .
GCN Circular 13560
Subject
GRB 120729A: Fermi GBM observation
Date
2012-08-02T12:40:37Z (13 years ago)
From
Arne Rau at MPE <arau@mpe.mpg.de>
Arne Rau (MPE) reports on behalf of the Fermi GBM Team:
"At 10:56:12.67 UT on 29 July 2012, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 120729A (trigger 365252175 / 120729456)
which was also detected by the Swift/BAT (Ukwatta et al. 2012, GCN 13530).
The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight is 83 degrees.
The GBM light curve shows a single pulse with a duration (T90) of about 25 s (50-300 keV).
The time-averaged spectrum from T0-3.6 s to T0+17.9 s is
best fit by a simple power law function with index -1.49 +/- 0.05.
The event fluence (10-1000 keV) in this time interval is
(5.1 +/- 0.1)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+1.2 s in the 10-1000 keV band
is 5.2 +/- 0.3 ph/s/cm^2.
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."
GCN Circular 13554
Subject
GRB 120729A: JCMT SCUBA-2 sub-mm observation
Date
2012-07-31T22:33:41Z (13 years ago)
From
Ian Smith at Rice U <ian@spacsun.rice.edu>
I.A. Smith (Rice U.), R.P.J. Tilanus (JAC), N.R. Tanvir (U. of Leicester),
D.A. Frail (NRAO) report:
We observed the location of GRB 120729A (Ukwatta et al., GCN Circ.
13530) using the SCUBA-2 sub-millimeter continuum camera on the James
Clerk Maxwell Telescope. The observation started at 12:14 UT on
2012-07-29, corresponding to 78 minutes after the burst trigger.
Exposures totaling 3.1 hours were made in reasonable weather conditions.
No source was detected, with a preliminary RMS of 1.8 mJy/beam at
850 microns.
We thank Jeff Cox and Ruud Visser for their prompt support of these
observations.
GCN Circular 13551
Subject
GRB 120729A: break in the optical light curve
Date
2012-07-31T11:06:32Z (13 years ago)
From
Andrea Melandri at INAF-OAB <andrea.melandri@brera.inaf.it>
P. D'Avanzo, A. Melandri (INAF-OAB), I. Steele, C.G. Mundell (LJMU),
E. Palazzi (INAF-IASFBo) report, on behalf of larger collaborations:
We observed the optical counterpart of GRB 120729A (Ukwatta et al.,
GCN 13530; Virgili et al., GCN 13531; Oates et al., GCN 13539; Wren et
al., GCN 13545) with the 2-m Faulkes Telescope North (FTN), the 2-m
Liverpool Telescope (LT) and with the Italian 3.6m Telescopio
Nazionale Galileo (TNG). Early time observations were carried out from
4.6 min to 2.1 hours after the burst with the FTN, while a later
observation epoch was taken at a mid time of about 14.5 hours after
the burst with the LT and the TNG.
From a preliminary analysis the overall R-band light curve can be
described by an initial power-law decay with an index of alpha1=1.0
that breaks around t-t0=6000 s to a steeper decay with alpha2=1.8. The
early time decay is consistent with the report of Wren et al. (GCN
13545).
The last detection was obtained with the TNG at a level of R ~ 23.3
mag (15.1 hours post burst) consistent with the marginal detections
obtained with LT SDSS-r filter (image acquired ~13.6 hours after the
burst). These late time values fall slightly below the best broken
power-law fit described above, suggesting that the post-break decay
index might be steeper than 2.
We note that the reported X-ray afterglow decay (Maselli et al., GCN
13541) shows a similar behaviour and that this may be indicative of an
achromatic break in the afterglow light curve.
We thank the TNG staff for performing the ToO observations, in
particular Massimo Cecconi.
GCN Circular 13550
Subject
GRB 120729A: Optical observations from OSN, BOOTES1/2 and IAC80
Date
2012-07-31T10:53:25Z (13 years ago)
From
Javier Gorosabel at IAA-CSIC <jgu@iaa.es>
J. Gorosabel (IAA-CSIC), M. Jelinek (IAA-CSIC), Ch. Wang (Yunnan
Observatory, China), C. Zurita (IAC), A. Sota (OSN, IAA-CSIC), J.C. Tello
(IAA-CSIC), R. Sanchez-Ramirez (IAA-CSIC), A.J. Castro-Tirado (IAA-CSIC),
report on behalf of a larger collaboration:
"We carried out BRI-band observations of the GRB 120729A (Ukwatta et al.
GCN Circ. 13530) optical afterglow (Virgili et al. GCN Circ. 13531; Oates
et al. GCN Circ. 13539) as follows:
Telescope Obs.Date(UT) Time post GRB(hr) Exp.Time(s) Mag.(Vega)
------------------------------------------------------------------------
0.3m Bootes-1B 29.879537-30.022106 10.17-13.58 326x30 R > 19.0
0.6m Bootes-2 30.007951-30.042095 13.25-14.07 50x60 R > 19.4
1.5m OSN 30.077613-30.163785 14.93-16.99 18x300 R > 22.1
1.5m OSN 30.096195-30.099667 15.37-15.45 1x300 B > 21.5
0.82m IAC80 30.120174-30.205093 15.95-17.98 22x300 I = 21.9+/-0.3
The calibration was based on the USNO B1.0 catalogue."
GCN Circular 13548
Subject
GRB 120729A: RTT150 optical observations
Date
2012-07-31T10:28:25Z (13 years ago)
From
Rodion Burenin at IKI, Moscow <rodion@hea.iki.rssi.ru>
I. Khamitov (TUG), E.Beklen (SD Uni.),
Z. Eker (TUG), U. Kiziloglu (METU), E. Gogus (Sabanci Uni.),
R. Burenin, M. Pavlinsky, R. Sunyaev (IKI),
I. Bikmaev, N. Sakhibullin (Kazan Federal University)
report:
We observed the field of the Swift-BAT GRB 120729A (Ukwatta et al. GCN
15530 ) with Russian-Turkish 1.5-m telescope (RTT150, Bakirlitepe,
TUBITAK National Observatory, Turkey), starting at 30 Jul, 01:26 UT,
i.e. approximately 14.5 hours after the burst, using TFOSC instrument.
We made 6x300s exposures in R-band under good atmospheric conditions
(1.4 arcsec seeing) at the beginning of morning twilight without
moonlight. We do not detect any new source on combined image at the
position of OT (Virgili et al., GCN13531; Oates and Ukwatta,
GCN13539). Using USNO-B1 stars we estimated the limiting magnitude of
combined image as m_R =~ 23.5.
A small field around of the OT position can be found at:
http://hea.iki.rssi.ru/grb/120729a/indexeng.html
GCN Circular 13547
Subject
GRB 120729A: EVLA Observations
Date
2012-07-31T02:39:04Z (13 years ago)
From
Tanmoy Laskar at Harvard U <tanmoylaskar@gmail.com>
T. Laskar, A. Zauderer and E. Berger (Harvard) report:
"We observed the position of GRB 120729A (Ukwatta et al. GCN 13530) with
the EVLA beginning 2012 July 30.3 UT (0.84 days after the burst). No
significant radio emission is detected at the enhanced Swift-XRT position
(Beardmore et al. GCN 13534), the UVOT position (Oates et al. GCN 13539) or
optical position (Virgili et al. GCN 13531) to three-sigma upper limits
of 39 uJy and 58 uJy, at 5.8 and 21.8 GHz, respectively."
GCN Circular 13546
Subject
Virtual Telescope observations of GRB 120729A
Date
2012-07-30T21:58:10Z (13 years ago)
From
Gianluca Masi at Bellatrix Astronomical Obs <gianluca@bellatrixobservatory.org>
G. Masi (Ceccano, Italy) and F. Nocentini (Frosinone, Italy) report:
On July 29.9496 2012 UT, we imaged the field around the position provided
by Ukwatta et al. (GCN 13530) with the 0.43m-f/6.8 unit part of the Virtual
Telescope robotic facility in Italy.
4, 300 seconds unfiltered CCD images were coadded and compared with a R plate
from the DSS2: they do NOT show any obvious afterglow, down to R = 20.0 (based
on USNO B1.0). The position of the afterglow mentioned on GCN 13530 is close to
a R=19.2 source (with end figures 18.28s and 23.2", J2000.0).
GCN Circular 13545
Subject
GRB 120729A: Early RAPTOR Observations
Date
2012-07-30T21:15:47Z (13 years ago)
From
James Wren at LANL <jwren@nis.lanl.gov>
J. Wren, P. Wozniak, H. Davis, and W.T. Vestrand
of Los Alamos National Laboratory report:
The RAPTOR network of robotic optical telescopes responded to Swift trigger
529095 (Ukwatta et al., GCN 13530