GRB 130831A
GCN Circular 18673
Subject
GRB 130831A: MASTER early OT detection and LC
Date
2015-12-07T14:17:09Z (10 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
E.Gorbovskoy, V. Lipunov, N.Tyurina, V.Kornilov,
P.Balanutsa, A.Kuznetsov, D.Kuvshinov
Lomonosov Moscow State University, Sternberg Astronomical Institute
K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk
Irkutsk State University
After this observation night there was no electricity at the
Tunka observatory for a few days . Therefore, the data were not immediately available. We
forgot to check the follow-up after power is restored and rediscovered
this source as optical transient during the data reprocessing of the
present time.
MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru)
located in Tunka was pointed to the GRB130831A 58 sec after trigger
time at 2013-08-31 13:05:14 UT. On our second (20s exposure 120 sec after
trigger) set we
found 1 optical transient within SWIFT error-box (ra=23 54 36 dec=+29 27
00 r=0.05) brighter then 15.1.
T-Tmid Date Time Expt. Ra Dec Mag
-------|-----------|----------|-------|-----------------|-----------------|-------
130 2013-08-31 13:06:16 20 23h 54m 29.82s +29d 25m 47.1s 14.34
The 5-sigma upper limit has been about 15.1mag
The automatic reduction data are below:
date time coord2000 Exp. Polaroid mag err
UT s
2013-08-31 13:05:13 - - 10 P/ >15.4
2013-08-31 13:05:14 - - 10 P\ >15.5
2013-08-31 13:06:14.969 23h 54m 29.77s +29d 25m 46s.5 20 P/ 14.19 0.13
2013-08-31 13:06:16.09 23h 54m 29.82s +29d 25m 47s.1 20 P\ 14.34 0.15
2013-08-31 13:07:37.707 23h 54m 29.94s +29d 25m 46s.6 40 P 13.70 0.07
2013-08-31 13:07:38.411 23h 54m 29.89s , +29d 25m 46s.3 40 P 14.08 0.08
2013-08-31 13:09:21.157 23h 54m 29.87s , +29d 25m 46s.5 60 P 13.96 0.06
2013-08-31 13:09:22.329 23h 54m 29.86s , +29d 25m 46s.3 60 P 14.17 0.06
2013-08-31 13:11:11.731 23h 54m 29.87s , +29d 25m 46s.8 80 P 13.96 0.05
2013-08-31 13:11:12.656 23h 54m 29.87s , +29d 25m 46s.4 80 P 14.05 0.04
2013-08-31 13:13:26.831 23h 54m 29.87s , +29d 25m 46s.4 110 P 13.14 0.02
2013-08-31 13:13:26.904 23h 54m 29.87s , +29d 25m 46s.7 110 P 13.23 0.01
2013-08-31 13:16:22.741 23h 54m 29.88s , +29d 25m 46s.4 140 P 12.76 0.01
2013-08-31 13:16:23.769 23h 54m 29.89s , +29d 25m 46s.7 140 P 12.79 0.01
2013-08-31 13:19:48.725 23h 54m 29.88s , +29d 25m 46s.5 180 P 13.10 0.01
2013-08-31 13:19:49.319 23h 54m 29.89s , +29d 25m 46s.6 180 P 13.03 0.01
2013-08-31 13:23:42.166 23h 54m 29.89s , +29d 25m 46s.6 180 P 13.44 0.01
2013-08-31 13:23:43.007 23h 54m 29.89s , +29d 25m 46s.6 180 P 13.40 0.01
2013-08-31 13:27:40.436 23h 54m 29.90s , +29d 25m 46s.5 180 P 13.80 0.01
2013-08-31 13:27:41.309 23h 54m 29.89s , +29d 25m 46s.7 180 P 13.79 0.01
2013-08-31 13:31:39.264 23h 54m 29.88s , +29d 25m 46s.7 180 P 14.08 0.02
2013-08-31 13:31:39.957 23h 54m 29.88s , +29d 25m 46s.8 180 P 14.12 0.01
2013-08-31 13:36:03.651 23h 54m 29.89s , +29d 25m 46s.4 180 P 14.44 0.02
2013-08-31 13:36:04.486 23h 54m 29.89s , +29d 25m 46s.5 180 P 14.51 0.02
2013-08-31 13:39:59.065 23h 54m 29.88s , +29d 25m 46s.6 180 P 14.55 0.02
2013-08-31 13:39:59.918 23h 54m 29.89s , +29d 25m 46s.7 180 P 14.53 0.02
2013-08-31 13:44:00.574 23h 54m 29.89s , +29d 25m 46s.7 180 P 14.72 0.02
2013-08-31 13:44:01.425 23h 54m 29.89s , +29d 25m 46s.6 180 P 14.78 0.03
2013-08-31 13:48:10.668 23h 54m 29.91s , +29d 25m 46s.5 180 P 14.94 0.03
2013-08-31 13:48:11.488 23h 54m 29.87s , +29d 25m 46s.5 180 P 14.95 0.02
2013-08-31 13:52:19.736 23h 54m 29.89s , +29d 25m 46s.3 180 P 14.97 0.03
2013-08-31 13:52:20.267 23h 54m 29.88s , +29d 25m 46s.3 180 P 14.99 0.03
2013-08-31 13:56:25.283 23h 54m 29.89s , +29d 25m 46s.7 180 P 15.11 0.03
2013-08-31 13:56:25.394 23h 54m 29.88s , +29d 25m 46s.6 180 P 15.05 0.03
2013-08-31 14:00:30.776 23h 54m 29.88s , +29d 25m 46s.7 180 P 15.16 0.03
2013-08-31 14:00:31.465 23h 54m 29.88s , +29d 25m 46s.6 180 P 15.13 0.03
2013-08-31 14:04:35.057 23h 54m 29.88s , +29d 25m 46s.5 180 P 15.18 0.03
2013-08-31 14:04:37.274 23h 54m 29.90s , +29d 25m 46s.8 180 P 15.10 0.03
2013-08-31 14:08:42.051 23h 54m 29.88s , +29d 25m 46s.6 180 P 15.18 0.03
2013-08-31 14:08:42.358 23h 54m 29.89s , +29d 25m 46s.8 180 P 15.18 0.03
2013-08-31 14:13:16.808 23h 54m 29.88s , +29d 25m 46s.5 180 P 15.16 0.03
2013-08-31 14:13:17.534 23h 54m 29.87s , +29d 25m 46s.6 180 P 15.19 0.03
2013-08-31 14:17:26.33 23h 54m 29.88s , +29d 25m 46s.6 180 P 15.22 0.03
2013-08-31 14:17:26.78 23h 54m 29.89s , +29d 25m 46s.7 180 P 15.16 0.03
2013-08-31 14:21:33.6 23h 54m 29.87s , +29d 25m 46s.4 180 P 15.33 0.03
2013-08-31 14:21:34.446 23h 54m 29.89s , +29d 25m 46s.6 180 P 15.27 0.03
2013-08-31 14:26:01.003 23h 54m 29.90s , +29d 25m 46s.7 180 P 15.37 0.03
2013-08-31 14:26:01.882 23h 54m 29.89s , +29d 25m 46s.5 180 P 15.30 0.03
2013-08-31 14:29:49.129 23h 54m 29.89s , +29d 25m 46s.7 180 P 15.45 0.03
2013-08-31 14:29:50.359 23h 54m 29.87s , +29d 25m 46s.7 180 P 15.39 0.03
2013-08-31 14:33:42.843 23h 54m 29.90s , +29d 25m 46s.4 180 P 15.47 0.03
2013-08-31 14:33:43.028 23h 54m 29.89s , +29d 25m 47s.0 180 P 15.46 0.04
2013-08-31 14:37:43.134 23h 54m 29.87s , +29d 25m 46s.4 180 P 15.52 0.04
2013-08-31 14:37:44.1 23h 54m 29.87s , +29d 25m 46s.6 180 P 15.42 0.04
2013-08-31 14:41:37.936 23h 54m 29.90s , +29d 25m 46s.5 180 P 15.66 0.04
2013-08-31 14:41:40.554 23h 54m 29.90s , +29d 25m 46s.5 180 P 15.57 0.04
2013-08-31 14:45:27.386 23h 54m 29.89s , +29d 25m 46s.4 180 P 15.71 0.04
2013-08-31 14:45:28.83 23h 54m 29.92s , +29d 25m 46s.7 180 P 15.54 0.04
2013-08-31 14:49:23.464 23h 54m 29.88s , +29d 25m 46s.6 180 P 15.70 0.04
2013-08-31 14:49:24.934 23h 54m 29.89s , +29d 25m 46s.6 180 P 15.58 0.04
2013-08-31 14:53:18.194 23h 54m 29.88s , +29d 25m 46s.4 180 P 15.66 0.04
2013-08-31 14:53:18.686 23h 54m 29.90s , +29d 25m 46s.8 180 P 15.58 0.04
2013-08-31 14:57:36.995 23h 54m 29.87s , +29d 25m 46s.3 180 P 15.76 0.04
2013-08-31 14:57:37.418 23h 54m 29.90s , +29d 25m 46s.6 180 P 15.63 0.04
2013-08-31 15:01:42.896 23h 54m 29.91s , +29d 25m 46s.3 180 P 15.88 0.05
2013-08-31 15:01:43.521 23h 54m 29.92s , +29d 25m 46s.6 180 P 15.69 0.04
2013-08-31 15:05:42.207 23h 54m 29.88s , +29d 25m 46s.6 180 P 15.95 0.04
2013-08-31 15:05:43.764 23h 54m 29.89s , +29d 25m 46s.7 180 P 15.75 0.04
2013-08-31 15:09:53.777 23h 54m 29.89s , +29d 25m 46s.4 180 P 15.93 0.05
2013-08-31 15:09:54.9 23h 54m 29.90s , +29d 25m 46s.5 180 P 15.84 0.05
2013-08-31 15:14:14.225 23h 54m 29.90s , +29d 25m 46s.5 180 P 16.04 0.05
2013-08-31 15:14:14.636 23h 54m 29.88s , +29d 25m 46s.5 180 P 15.90 0.05
2013-08-31 15:18:32.515 23h 54m 29.88s , +29d 25m 46s.4 180 P 15.98 0.05
2013-08-31 15:18:32.972 23h 54m 29.62s , +29d 25m 46s.7 180 P 16.80 0.08
2013-08-31 15:22:42.728 23h 54m 29.86s , +29d 25m 46s.4 180 P 16.13 0.05
2013-08-31 15:22:43.005 23h 54m 29.72s , +29d 25m 47s.5 180 P 16.50 0.08
2013-08-31 15:27:06.639 23h 54m 29.88s , +29d 25m 46s.1 180 P 16.23 0.06
2013-08-31 15:27:07.166 23h 54m 29.90s , +29d 25m 46s.6 180 P 15.99 0.06
2013-08-31 15:31:14.164 23h 54m 29.89s , +29d 25m 46s.5 180 P 16.32 0.06
2013-08-31 15:31:14.663 23h 54m 29.89s , +29d 25m 47s.1 180 P 16.06 0.06
2013-08-31 15:35:08.964 23h 54m 29.87s , +29d 25m 46s.4 180 P 16.39 0.07
2013-08-31 15:35:10.803 23h 54m 29.97s , +29d 25m 49s.0 180 P 16.83 0.10
2013-08-31 15:39:37.457 23h 54m 29.89s , +29d 25m 46s.7 180 P 16.47 0.07
2013-08-31 15:39:38.229 23h 54m 29.84s , +29d 25m 48s.1 180 P 16.73 0.10
2013-08-31 15:43:50.963 23h 54m 29.89s , +29d 25m 46s.6 180 P 16.51 0.07
2013-08-31 15:43:51.628 23h 54m 29.68s , +29d 25m 46s.2 180 P 17.30 0.14
2013-08-31 15:47:41.439 23h 54m 29.92s , +29d 25m 46s.8 180 P 16.41 0.08
2013-08-31 15:47:41.868 23h 54m 29.70s , +29d 25m 46s.3 180 P 16.70 0.10
2013-08-31 15:51:28.744 23h 54m 29.89s , +29d 25m 46s.7 180 P 16.57 0.08
2013-08-31 15:51:29.974 23h 54m 29.69s , +29d 25m 45s.8 180 P 16.99 0.12
2013-08-31 15:55:28.935 23h 54m 29.91s , +29d 25m 46s.6 180 P 16.68 0.11
2013-08-31 15:55:29.91 23h 54m 29.92s , +29d 25m 46s.6 180 P 16.36 0.10
2013-08-31 15:59:32.081 23h 54m 29.88s , +29d 25m 46s.5 180 P 16.78 0.09
2013-08-31 15:59:32.882 23h 54m 29.77s , +29d 25m 45s.2 180 P 16.75 0.10
2013-08-31 16:03:45.019 23h 54m 29.89s , +29d 25m 46s.2 180 P 16.71 0.09
2013-08-31 16:03:45.878 23h 54m 29.73s , +29d 25m 49s.2 180 P 16.98 0.13
2013-08-31 16:03:45.878 23h 54m 29.67s , +29d 25m 45s.0 180 P 17.21 0.14
2013-08-31 16:07:40.752 23h 54m 29.87s , +29d 25m 46s.7 180 P 16.68 0.10
2013-08-31 16:07:40.756 23h 54m 29.85s , +29d 25m 46s.9 180 P 16.53 0.11
2013-08-31 16:11:45.003 23h 54m 29.89s , +29d 25m 46s.5 180 P 16.65 0.09
2013-08-31 16:11:46.074 23h 54m 29.68s , +29d 25m 47s.0 180 P 16.51 0.11
2013-08-31 16:16:04.472 23h 54m 29.89s , +29d 25m 46s.2 180 P 16.90 0.11
2013-08-31 16:16:05.21 23h 54m 29.71s , +29d 25m 46s.2 180 P 17.15 0.14
2013-08-31 16:20:16.552 23h 54m 29.88s , +29d 25m 46s.4 180 P 16.71 0.09
2013-08-31 16:20:16.892 23h 54m 29.90s , +29d 25m 47s.3 180 P 16.63 0.12
2013-08-31 16:24:28.011 23h 54m 29.92s , +29d 25m 46s.2 180 P 16.74 0.12
2013-08-31 16:24:28.419 23h 54m 29.64s , +29d 25m 46s.9 180 P 17.97 0.22
2013-08-31 16:28:38.273 23h 54m 29.91s , +29d 25m 46s.3 180 P 16.75 0.11
2013-08-31 16:28:39.181 23h 54m 29.66s , +29d 25m 47s.7 180 P 17.10 0.16
2013-08-31 16:32:35.03 23h 54m 29.88s , +29d 25m 46s.4 180 P 17.03 0.12
2013-08-31 16:36:41.311 23h 54m 29.91s , +29d 25m 46s.9 180 P 16.88 0.13
2013-08-31 16:36:41.982 23h 54m 29.90s , +29d 25m 45s.2 180 P 16.91 0.14
2013-08-31 16:40:40.333 23h 54m 29.85s , +29d 25m 46s.5 180 P 17.07 0.15
2013-08-31 16:40:40.788 23h 54m 29.80s , +29d 25m 46s.5 180 P 18.57 0.32
The automatic light curve is available at
http://observ.pereplet.ru/images/GRB130831A.jpg
The message may be cited.
GCN Circular 15321
Subject
GRB 130831A: Continued RATIR Optical and NIR Observations
Date
2013-10-09T21:22:00Z (12 years ago)
Edited On
2024-11-07T18:49:55Z (a year ago)
From
Alan M. Watson at Instituto de Astronomia UNAM <alan@astro.unam.mx>
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>
William H. Lee (UNAM), Nat Butler (ASU), Alan M. Watson (UNAM),
Alexander Kutyrev (GSFC), Michael G. Richer (UNAM), Chris Klein (UCB),
Ori Fox (UCB), J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino
Cucchiara (UCSC), Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico
Ramirez-Ruiz (UCSC), José A. de Diego (UNAM), Leonid Georgiev (UNAM),
Jesús González (UNAM), Carlos Román-Zúñiga (UNAM), Neil Gehrels (GSFC),
and Harvey Moseley (GSFC) report:
We observed the field of GRB 130831A (Hagen, et al., GCN 15139) with the
Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the
1.5m Harold Johnson Telescope at the Observatorio Astronómico Nacional on
Sierra San Pedro Mártir from 2013/10 9.10 to 2013/10 9.47 UTC (925.41
to 934.19 hours after the BAT trigger), obtaining a total of 6.08 hours
exposure in the r and i bands and 2.61 hours exposure in the Z,
Y, J, and H bands.
For a source within the Swift-XRT error circle, in comparison with 2MASS, we
obtain the following upper limits (3-sigma):
r > 24.14
i > 23.63
Z > 22.94
Y > 22.45
J > 22.23
H > 21.74
These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.
As compared with our previous RATIR observations (Lee et al., GCN 15274) we
confirm the fading in r and i by at least 0.3 and 0.4 and magnitudes, respectively.
The upper limits in Z, Y, J, and H are also consistent with fading.
Overall our measurements (Butler et al. GCN 15165, Watson et al. GCN 15179,
Lee et al., GCN 15242, 15274) are consistent with the re-brightening due to
a SN, as reported by Pozanenko et al. (GCN 15237) and spectroscopically by
Klose et al. (GCN 15320), and fading.
We thank the staff of the Observatorio Astronómico Nacional in San Pedro
Mártir.
GCN Circular 15320
Subject
GRB 130831A: VLT/FORS2 spectroscopic detection of a supernova
Date
2013-10-09T09:54:39Z (12 years ago)
From
Sylvio Klose at TLS Tautenburg <klose@tls-tautenburg.de>
S. Klose, A. Nicuesa Guelbenzu (both TLS Tautenburg), T. Kruehler (ESO),
J. Greiner, D. A. Kann, A. Rau, V. Sudilovsky (all MPE Garching), F. Olivares E. (UNAB,
MCSS, Chile), and S. Schulze (PUC, MCSS, Chile), on behalf of a larger
collaboration report:
We observed the optical transient following GRB 130831A (e.g., Hagen et
al. 2013, GCN 15139; Guidorzi et al. 2013, GCN 15140; Xu et al. 2013, GCN
15142; Yoshii et al. 2013, GCN 15143) with VLT/FORS2 equipped with the
300V grism on Sep 29 and Sep 30, 2013, between 28.5 and 29.5 days after
the burst under excellent sky conditions with mean seeing around 0.6". The
total exposure time of the spectrum was 1.53 hr and covers the spectral
range between approximately 440 and 920 nm.
In the combined spectrum, we detect the optical emission over the full
spectral range. The spectrum peaks at about 800 nm and shows broad
absorption features, very much reminiscent of the spectrum of, e.g., GRB
031203 / SN 2003lw (z=0.1055; Malesani et al. 2004, ApJ 609, L5), and the
recent GRB 120714B / SN 2012eb (z=0.40; Klose et al. 2012, GCN 13613), GRB
130215A / SN 2013ez (z=0.597; de Ugarte Postigo et al., GCN 14303), GRB
130427A / SN 2013cq (z=0.34; Xu et al. 2013, ApJ 776, 98), and GRB 130702
/ SN 2013dx (z=0.145; Schulze et al. 2013, GCN 14994), all obtained around
SN maximum light.
We conclude that we have spectroscopically discovered the appearence of a
broad-line SN following GRB 130831A at z=0.4791 (Cucchiara et al. 2013,
GCN 15144), confirming the conclusion of Pozanenko et al. (GCN 15237)
based on the optical light curve.
[GCN OPS NOTE(12oct13): Per author's request, VS was added to the author list.]
GCN Circular 15274
Subject
GRB 130831A: Continued RATIR Optical and NIR Observations
Date
2013-09-30T16:17:13Z (12 years ago)
Edited On
2024-11-07T19:35:07Z (a year ago)
From
Nat Butler at Az State U <natbutler@asu.edu>
Edited By
Vidushi Sharma at NASA GSFC/UMBC <vidushi.sharma@nasa.gov> on behalf of Leo P. Singer at NASA/GSFC <leo.p.singer@nasa.gov>
William H. Lee (UNAM), Alan M. Watson (UNAM), Alexander Kutyrev (GSFC), Nat
Butler (ASU), Michael G. Richer (UNAM), Chris Klein (UCB), Ori Fox (UCB),
J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UCSC),
Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC),
José A. de Diego (UNAM), Leonid Georgiev (UNAM), Jesús González (UNAM),
Carlos Román-Zúñiga (UNAM), Neil Gehrels (GSFC), and Harvey Moseley (GSFC)
report:
We observed the field of GRB 130831A (Hagen, et al., GCN 15139) with the
Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the
1.5m Harold Johnson Telescope at the Observatorio Astronómico Nacional on
Sierra San Pedro Mártir from 2013/09 30.12 to 2013/09 30.49 UTC (29.58 to
29.94 days after the BAT trigger), obtaining a total of 6.27 hours exposure
in the r and i bands and 2.65 hours exposure in the Z, Y, J, and H bands.
For a source within the Swift-XRT error circle (Evans et al., GCN 15147),
in comparison with 2MASS, we obtain the following detections and upper
limits (3-sigma):
r 23.84 +/- 0.18
i 23.23 +/- 0.15
Z > 23.04
Y > 22.53
J > 22.37
H > 21.72
These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB. The source has faded relative to
our last measurement (t~21.5 days; Lee et al., GCN 15242) by about 0.8
magnitudes in r and J and 0.5 magnitudes in i. Our measurements (see,
also, Watson et al., GCN 15179; Butler et al., GCN 15165) are consistent
with a bump or re-brightening in the lightcurve at t~10 days (see,
Pozanenko et al., GCN 15237), followed by continued fading.
We thank the staff of the Observatorio Astronómico Nacional in San Pedro
Mártir.
GCN Circular 15244
Subject
GRB 130831A: RTT150 optical observations
Date
2013-09-23T12:08:11Z (12 years ago)
From
Rodion Burenin at IKI, Moscow <rodion@hea.iki.rssi.ru>
G. Khorunzhev, R. Burenin, M. Pavlinsky, R. Sunyaev (IKI),
I. Bikmaev, N. Sakhibullin (KFU/AST),
I. Khamitov, H. Kirbiyik (TUG)
report:
The optical afterglow of GRB 130831A (GCN 15139, D. Palmer) was
observed with 1.5-m Russian-Turkish Telescope RTT150 at Bakyrlytepe
(TUBITAK National Observatory, Turkey). The observation started at
2013-09-01 00:42:03 UT, appr. 12 hours after the burst.
Two images each with exposure 300 seconds were obtained in R-band:
1. UT = 00:42:03.678; t-t0 = 11.630h; m_R = 19.57 +- 0.02
2. UT = 00:48:35.373; t-t0 = 11.739h; m_R = 19.62 +- 0.03
Images are calibrated using stars proposed by Pozanenko et al. (GCN
15190). The magnitudes are not corrected for the Galactic extinction.
GCN Circular 15242
Subject
GRB 130831A: RATIR Confirmation of NIR/Optical Afterglow Flattening
Date
2013-09-22T15:05:22Z (12 years ago)
Edited On
2024-11-07T19:52:48Z (a year ago)
From
Nat Butler at Az State U <natbutler@asu.edu>
Edited By
Vidushi Sharma at NASA GSFC/UMBC <vidushi.sharma@nasa.gov> on behalf of Leo P. Singer at NASA/GSFC <leo.p.singer@nasa.gov>
William H. Lee (UNAM), Alan M. Watson (UNAM), Nat Butler (ASU), Alexander
Kutyrev (GSFC), Michael G. Richer (UNAM), Chris Klein (UCB), Ori Fox (UCB),
J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UCSC),
Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC),
José A. de Diego (UNAM), Leonid Georgiev (UNAM), Jesús González (UNAM),
Carlos Román-Zúñiga (UNAM), Neil Gehrels (GSFC), and Harvey Moseley (GSFC)
report:
We again observed the field of GRB 130831A (Hagen, et al., GCN 15139) with
the Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on
the 1.5m Harold Johnson Telescope at the Observatorio Astronómico Nacional
on Sierra San Pedro Mártir from 2013/09 22.11 to 2013/09 22.31 UTC (21.57
to 21.77 days after the BAT trigger), obtaining a total of 6.40 hours
exposure in the r and i bands and 2.60 hours exposure in the Z, Y, J, and H
bands.
For a source within the Swift-XRT error circle (Evans et al., GCN 15147),
in comparison with SDSS DR9 and 2MASS, we obtain the following detections
and upper limits (3-sigma):
r 23.02 +/- 0.14
i 22.78 +/- 0.13
Z > 22.87
Y > 22.35
J 21.62 +/- 0.19
H > 21.75
These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB. The flux levels are consistent
with our prior upper limits measured 4 days after the GRB (Butler et al.,
GCN 15179) and with the measurements reported by Pozanenko et al. (GCN
15237), confirming a flattening of the afterglow light curve.
We thank the staff of the Observatorio Astronómico Nacional in San Pedro
Mártir.
GCN Circular 15237
Subject
GRB 130831A: Maidanak optical observations, possible emerging Supernova
Date
2013-09-21T12:04:06Z (12 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
A. Pozanenko (IKI), A. Volnova (IKI), B. Hafizov (UBAI), O. Burhonov
(UBAI) report on behalf of larger GRB follow-up collaboration:
We continue observation of the afterglow (Hagen et al., GCN 15139;
Guidorzi et al., GCN 15140) of the Swift GRB 130831A (Hagen et al., GCN
15139) with AZT-22 telescope equipped with SNUCAM at Maidanak
observatory. A preliminary photometry of combined images obtained on
Sep. 16 is following:
T_start T0+ Filter, Exposure, OT
(UT) (mid, d) (s)
2013-09-16T19:00:13 16.28 R 14x300 22.77 +/- 0.07
The photometry is based on SDSS stars (see GCN 15190).
This is brighter than we obtained on Sep. 9 (23.11 +/- 0.06) and on
Sep. 15 (22.87 +/- 0.08). We suggest the observed re-brightening is an
emerging Supernova associated with GRB 130831A.
A preliminary lc of the afterglow+SN of GRB 130831A can be found in
http://grb.rssi.ru/GRB130831A/grb130831A_lc_preliminary.PNG
GCN Circular 15190
Subject
GRB 130831A: Maidanak optical observations
Date
2013-09-08T00:17:41Z (12 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
A. Pozanenko (IKI), A. Volnova (IKI), B. Hafizov (UBAI), O. Burhonov
(UBAI) report on behalf of larger GRB follow-up collaboration:
We observed the afterglow (Hagen et al., GCN 15139