GRB 160925A
GCN Circular 20006
Subject
GRB 160925A: Kottamia R-band observation
Date
2016-10-06T23:05:13Z (10 years ago)
From
Gamal B. Ali at NRIAG <gamalali@lycos.com>
G. B. Ali, Y. Hendy, A. Takey, N. Essam, and A. Essam (NRIAG, Egypt)
report on behalf of the Kottamia collaboration:
We observed the field of the Fermi GRB 160925A (trigger #496473540) with
the 1.88m telescope of the KAO (Kottamia Astronomical Observatory),
Egypt. The observation was performed in the Rc-band at the Newtonian
camera (F4.8) and started at 2016-09-29 T19:58:17 UT (~4.08 day after
the burst).
We obtained several exposures in the Rc-band each one with 300s exposure
time. We clearly detected the optical transient (Lipunov et al., GCN
19938; Guidorzi et al., GCN 19939).
The following accurate photometry is obtained for the transient:
UT (Start) Rc error*
2016-09-29T19:58:17 17.260 0.011
2016-09-29T20:03:31 17.232 0.011
2016-09-29T20:08:42 17.252 0.012
2016-09-29T20:13:53 17.326 0.013
2016-09-29T20:19:04 17.267 0.012
2016-09-29T20:24:15 17.223 0.011
2016-09-29T20:29:26 17.305 0.011
2016-09-29T20:34:37 17.281 0.012
2016-09-29T20:39:48 17.239 0.011
----------------------------------------------------
(*) Poisson noise error only.
The Photometric calibration is based on nearby USNO-B1.0 stars
USNO-B1.0 R2
0750-0813981 13.69
0750-0813991 14.20
0750-0813958 14.93
0750-0813917 15.62
[GCN OPS NOTE(08oct16): Per author's request, the signature block and the appended
copy of the 19947 circular have been removed.]
GCN Circular 19948
Subject
XRT refined analysis for GRB 160925A
Date
2016-09-27T15:01:49Z (10 years ago)
From
Boris Sbarufatti at INAF-OAB/IASFPA <boris.sbarufatti@brera.inaf.it>
J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), V. D���Elia (ASDC), A. D'Ai (INAF-IASFPA), A. Melandri (INAF-OAB), T.G.R. Roegiers (PSU), L.M. McCauley (PSU), J.A. Kennea (PSU), B. Mingo (U. Leicester) and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team:
Swift-XRT has performed follow-up observations of the Fermi/GBM-detected burst GRB 160925A, pointing towards the direction of the MASTER variable optical source (Lipunov et al., GCN 19938), collecting 3.0 ks of Photon Counting (PC) mode data between T0+122.7 ks and T0+133.6 ks.
No X-ray sources have been detected consistent with being within 9.9 arcsec of the MASTER position. The 3-sigma upper limit in the field is 0.003 ct s^-1, corresponding to a 0.3-10 keV observed flux of 1.1e-13 erg cm^-2 s^-1 (assuming a typical GRB spectrum).
The lack of X-ray detection is consistent with the classification of the optical source as a dwarf nova (Steele et al., GCN 19944).
The results of the XRT-team automatic analysis of the XRT observations, including a position-specific upper limit calculator, are available at http://www.swift.ac.uk/ToO_GRBs/00020701.
This circular is an official product of the Swift-XRT team.
GCN Circular 19947
Subject
GRB 160925A/MASTER optical transient: Mondy optical observations
Date
2016-09-27T12:34:06Z (10 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Mazaeva (IKI), A. Pozanenko (IKI), E. Klunko (ISTP), A. Volnova
(IKI), I. Korobtsev (ISTP) report on behalf of larger GRB follow-up
collaboration:
We observed the field of the Fermi GRB 160925A (trigger #496473540) with
AZT-33IK telescope of Sayan observatory (Mondy) starting on Sep., 26
(UT) 14:38:09. We obtained several images in R-filter. We clearly
detected optical transient (Lipunov et al., GCN 19938; Guidorzi et al.,
GCN 19939). Preliminary photometry of the transient is following
Date UT start t-T0 Filter Exp. OT UpLim (3 sigma)
(mid, days) (s)
2016-09-26 14:38:09 0.88014 R 30*120 16.06+/-0.03 23.0
Photometry is based on nearby USNO-B1.0 stars
USNO-B1.0 R2
0750-0813972 16.86
0750-0813954 17.70
0750-0813947 17.78
GCN Circular 19946
Subject
GRB 160925A: MITSuME Akeno Optical Observations
Date
2016-09-27T10:33:25Z (10 years ago)
From
Taketoshi Yoshii at Tokyo Tech <yoshii.t.ac@m.titech.ac.jp>
T.Fujiwara, T. Yoshii, Y.Saito, R.Itoh, Y. Tachibana,
Y.Ono, S.Harita, T.Ozawa, K.Saisho, Y. Yatsu, and N. Kawai (Tokyo Tech)
report on behalf of the MITSuME collaboration:
We observed the field of GRB 160925A (C. Guidorzi et al., GCN
Circular #19939) with the optical three color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm
telescope of Akeno Observatory, Yamanashi, Japan.
The observation started on 2016-09-26 12:21:13 UT (~0.75 day after the burst) and
we detected the optical counterpart in Rc and Ic band.
The measured magnitudes were listed as follows.
We obtained following results for the magnitudes.
T0+[day] MID-UT T-EXP[sec] g' Rc Ic
-------------------------------------------------------------------------------------------------------
0.75 12:53:24 480 15.96 +/- 0.04 16.00 +/- 0.05 15.93 +/- 0.06
-------------------------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time
We used GSC2.3 catalog for flux calibration.
GCN Circular 19945
Subject
GRB 160925A: Bassano Bresciano Photometry of MASTER optical transient
Date
2016-09-27T09:44:27Z (10 years ago)
From
Ulisse Quadri at Bassano Bresciano Obs <oabb@ulisse.bs.it>
U.Quadri, L.Strabla and R.Girelli report:
The photometrical observations of the MASTER optical transient (GCN 19938, 19939, 19941)
Is it a possible optical counterpart to the FERMI GBM trigger 496473540 (GRB160925A).
The optical transient has the ID MASTER OT J222817.90-145657.4.
Observations made by the 250 mm F/4.8 Newton robotic telescope of
(IAU station 565) Bassano Bresciano Observatory.
Observations started on 2016-09-26 at 20h 04m UT and ended 2016-09-26 at 22h 32m UT
Exposures time of 60 sec each.
Reference star is: UCAC4 376-178184
Chk Star is: UCAC4 375-181914
------------------------------------
CV Mag.
T (JD)" OT Chk1
------------------------------------
2457658.33643518 16.089 13.981
2457658.33721064 15.947 13.953
2457658.33797453 16.051 13.976
2457658.33875000 16.019 13.962
2457658.33952546 16.026 13.991
2457658.34030092 15.986 13.963
2457658.34107638 16.060 13.968
2457658.34185185 16.065 13.969
2457658.34262731 16.132 13.977
2457658.34339120 16.060 13.991
2457658.34439814 16.072 13.973
2457658.34516203 15.988 13.983
2457658.34592592 16.043 13.959
2457658.34668981 16.069 13.981
2457658.34745370 15.963 14.002
2457658.34840277 16.083 13.969
2457658.34916666 16.035 13.958
2457658.34991898 16.068 13.963
2457658.35069444 16.054 13.989
2457658.35144675 15.944 13.975
2457658.35239583 15.962 13.986
2457658.35315972 16.040 14.013
2457658.35392361 16.072 13.995
2457658.35468749 15.956 13.976
2457658.35543981 15.983 13.990
2457658.35638888 15.992 13.980
2457658.35715277 16.010 13.969
2457658.35791666 15.996 13.990
2457658.35868055 15.974 13.971
2457658.35944444 15.992 13.989
2457658.36039351 16.111 13.952
2457658.36114583 16.004 14.008
2457658.36190972 15.980 13.991
2457658.36267361 15.939 13.978
2457658.36343749 16.035 14.001
2457658.36438657 15.972 13.985
2457658.36515046 16.028 13.989
2457658.36591435 16.055 13.989
2457658.36667824 16.063 13.989
2457658.36743055 16.015 13.987
2457658.36837962 16.036 13.976
2457658.36914351 15.971 13.997
2457658.36990740 15.935 13.997
2457658.37067129 16.016 13.963
2457658.37143518 16.077 14.017
2457658.37238425 15.977 13.968
2457658.37314814 15.985 13.995
2457658.37391203 15.905 13.959
2457658.37466435 15.941 13.974
2457658.37542824 15.998 13.982
2457658.37637731 16.002 13.971
2457658.37714120 15.934 13.970
2457658.37790509 15.859 13.949
2457658.37866898 15.994 13.950
2457658.37942129 16.021 13.966
2457658.38037037 16.015 13.978
2457658.38113425 16.142 13.966
2457658.38189814 15.944 14.019
2457658.38266203 16.022 13.975
2457658.38342592 16.174 13.992
2457658.38436342 16.119 14.019
2457658.38512731 16.109 13.959
2457658.38589120 16.112 13.966
2457658.38665509 15.908 13.963
2457658.38740740 16.054 13.975
2457658.38835648 16.030 13.987
2457658.38912037 16.184 13.968
2457658.39633101 16.020 14.001
2457658.39709490 15.941 13.967
2457658.39785879 16.160 13.989
2457658.39863425 15.937 13.958
2457658.39938657 16.069 13.992
2457658.40033564 16.051 13.993
2457658.40262731 16.062 13.963
2457658.40908564 15.910 14.006
2457658.40984953 16.049 13.979
2457658.41061342 16.024 13.953
2457658.41231481 16.074 13.989
2457658.41307870 16.090 13.996
2457658.41384259 15.901 13.986
2457658.41460648 16.137 13.986
2457658.41537037 16.033 13.994
2457658.41631944 16.053 13.972
2457658.41708333 16.132 13.979
2457658.41783564 16.025 13.963
2457658.41859953 16.029 13.968
2457658.41936342 16.067 13.987
2457658.42031250 16.031 13.965
2457658.42107638 16.007 13.978
2457658.42184027 16.031 13.950
2457658.42260416 15.986 13.958
2457658.42335648 16.055 13.939
2457658.42430555 16.011 13.949
2457658.42506944 15.992 13.983
2457658.42583333 15.966 13.978
2457658.42736111 16.004 13.967
2457658.42829861 16.053 13.975
2457658.42906250 16.132 13.953
2457658.42982638 15.971 13.933
2457658.43059027 16.006 13.955
2457658.43135416 16.138 13.985
2457658.43229166 15.972 13.962
2457658.43305555 15.962 13.966
2457658.43381944 16.082 13.962
2457658.43458333 15.992 13.944
2457658.43534722 15.873 13.947
2457658.43628472 15.986 13.972
2457658.43781250 16.153 13.968
2457658.43857638 16.018 13.957
Magnitudes were estimated with the UCAC4 cat. and
are not corrected for galactic dust extinction.
Reference: http://www.osservatoriobassano.org/GRB.asp
The message may be cited.
GCN Circular 19944
Subject
GRB 160925A: Optical spectroscopy of MASTER optical transient
Date
2016-09-27T08:53:03Z (10 years ago)
From
Cristiano Guidorzi at Ferrara U,Italy <guidorzi@fe.infn.it>
I.A.Steele (LJMU), C. Guidorzi (U. Ferrara), C. G. Mundell (Bath), A. Gomboc (U. Nova Gorica), J. Japelj (INAF-OAT) report on behalf of a larger collaboration.
We report optical spectroscopy of the MASTER optical transient (GCN 19938, 19939, 19941) which is a possible optical counterpart to the FERMI GBM trigger 496473540 (GRB160925A).
The optical transient has the ID MASTER OT J222817.90-145657.4.
A low resolution (R~350) optical (400-800nm) spectrum was obtained using the SPRAT spectrograph of the Liverpool Telescope (La Palma) on 26-09-16 at 21:25:49 UT. The 300 second exposure shows a strong, blue continuum with clear H-beta and H-gamma absorption lines at zero redshift. H-alpha is not present either in emission or absorption (implying a degree of H-alpha emission). The spectrum is consistent with a dwarf nova during outburst and therefore not likely to be associated with the Fermi trigger.
GCN Circular 19941
Subject
GRB 160925A / Fermi 496473540: MASTER OT observations
Date
2016-09-26T16:34:17Z (10 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
V. Lipunov,
Lomonosov Moscow State University, Sternberg Astronomical Institute
We continued observation of MASTER OT J222817.90-145657.4 , detected by
MASTER inside FERMI GBM trigger 496473540 (Lipunov et al., GCN 19938)
error box. The OT light curve from MASTER-SAAO is
available at
http://observ.pereplet.ru/images/MASTEROTJ222817.90-145657.4.jpg
and looks like dwarf novae outburst (amplitude more then 6.1m).
The message may be cited.
GCN Circular 19940
Subject
GRB 160925A: Swift ToO observations
Date
2016-09-26T15:36:15Z (10 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
P. A. Evans (U. Leicester) reports on behalf of the Swift team:
Swift has initiated a ToO observation of the Fermi/GBM/MASTER GRB 160925A.
Automated analysis of the XRT data will be presented online at
http://www.swift.ac.uk/ToO_GRBs/00020701
Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. These are
not necessarily related to the Fermi/GBM/MASTER event. Any X-ray source
considered to be a probable afterglow candidate will be reported via a
GCN Circular after manual consideration.
Details of the XRT automated analysis methods are detailed in Evans et
al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).
This circular is an official product of the Swift-XRT team.
GCN Circular 19939
Subject
GRB160925A / Fermi 496473540: MASTER optical transient confirmation by LCOGT-FTN
Date
2016-09-26T10:26:53Z (10 years ago)
From
Cristiano Guidorzi at Ferrara U,Italy <guidorzi@fe.infn.it>
C. Guidorzi (U. Ferrara), S. Kobayashi, I.A. Steele (LJMU), C.G. Mundell
(U. Bath), A. Gomboc (U. Nova Gorica) on behalf of a large collaboration
report:
The 2-m LCOGT Faulkes Telescope North began observing the MASTER optical
transient possibly associated to GRB160925A/Fermi 496473540 (Lipunov et
al., GCN 19938) on September 26, 08:11 UT (0.6 days since MASTER
observations). We confirm the presence of an uncatalogued object at the
following position:
RA(J2000)= 22:28:17.82
Dec(J2000)= -14:56:56.6
with an uncertainty of 1.0 arcsec and R=16.17 +- 0.01 mag, I=16.00+-0.01
mag, as calibrated against USNOB-1 star 22:28:23.443, -14:57:33.95 using
R2=13.69 mag, I=13.00 mag.
Given its ecliptic coordinates (333 deg, -5 deg), with reference to the
IAU Minor Planet Center we checked that there is no known minor planet
or comet brighter than V=20.0 mag within 10 arcminutes at the epoch of
our observations.
GCN Circular 19938
Subject
GRB 160925A / Fermi 496473540: Global MASTER Net OT discovery
Date
2016-09-26T07:51:33Z (10 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
V. Lipunov, O.Gress, N.Tyurina, E. Gorbovskoy, V.Kornilov,
P.Balanutsa, A.Kuznetsov, D.Kuvshinov
Lomonosov Moscow State University, Sternberg Astronomical Institute
D.Buckley, S. Potter,
South African Astronomical Observatory
H. Levato, C. Saffe
Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)
R.Podesta, C.Lopez, F. Podesta
Observatorio Astronomico Felix Aguilar (OAFA)
R. Rebolo, M. Serra Ricart, N. Lodieu, G. Israelian
The Instituto de Astrofisica de Canarias
K.Ivanov, J.Rabinovich, N.M.Budnev,
Irkutsk State University
A. Tlatov, V.Senik, D. Dormidontov, A.Parkhomenko
Kislovodsk Solar Station of the Pulkovo Observatory
V.Yurkov, Yu.Sergienko, A.Gabovich
Blagoveschensk Educational State University, Blagoveschensk
MASTER-SAAO robotic telescope (MASTER-Net: http://observ.pereplet.ru)
pointed to the FERMI GBM trigger 496473540 (GRB160925A ) at 2016-09-25
2016-09-25 18:00:46 UT and automatically started inspection (there was a
day at the trigger time 05:18:56.45UT).
MASTER-SAAO auto-detection system discovered OT source at
(RA, Dec) = 22h 28m 17.90s -14d 56m 57.4s
on 2016-09-25.75053 UT with unfiltered magnitude m_OT=15.9m (mlim=19.7m),
Bmag=15.3, Imag=15.9 (Gress et al. ATEL #9548).
There is no any known sources inside 5" in VIZIER database, it gives
amplitude of current outburst more then 6mag.
The discovery and reference images are available at
http://master.sai.msu.ru/static/OT/222817.90-145657.4.png
Spectral observations are required.
The message may be cited.