GRB 181228A
GCN Circular 23669
Subject
GRB 181228A: FRAM-ORM optical limit
Date
2019-01-10T07:26:40Z (7 years ago)
From
Martin Jelinek at Astro.Inst-AVCR,Ondrejov <martin.jelinek@asu.cas.cz>
Martin Jelinek and Jan Strobl (ASU CAS Ondrejov, CZ),
Martin Masek, Petr Janecek, Sergey Karpov, Jakub Jurysek,
Jan Ebr, Ronan Cunniffe, Petr Travnicek and Michael Prouza
(Institute of Physics, Prague, CZ)
report:
The 25cm robotic telescope FRAM-ORM at La Palma (Spain)
reacted robotically to the alert of GRB181228A (Moss et
al, GCNC 23570), obtaining a series of 20s R-band images
starting at 02:53:51.1UT, i.e. 34s post trigger.
We do not detect any new source in comparison to USNO-B1.0
catalog neither in single images (3-sigma limit R>~17.1)
nor in a combined 20x20s frame (mean exp time 269s post
trigger, 3-sigma limit R>~18.7).
Martin Jel��nek, +420602105255, +34617840945, lascaux.asu.cas.cz/mates
Astronomick�� ��stav AV��R, Ond��ejov
GCN Circular 23596
Subject
GRB 181228A: Mondy and AbAO optical upper limits
Date
2018-12-31T17:37:10Z (7 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
S. Belkin (IKI), A. Pozanenko (IKI), E. Klunko (ISTP), R. Ya. Inasaridze
(AbAO), E. Mazaeva (IKI), A. Volnova (IKI), V. R. Ayvazian (AbAO),
G. V. Kapanadze (AbAO) report on behalf of the IKI GRB-FuN:
We observed the field of GRB 181228A (Moss et al., GCN 23570; Beardmore
et al., GCN 23574) with AZT-33IK telescope of Sayan observatory (Mondy)
starting on Dec. 28 (UT) 13:48:11 in I-filter, and AS-32 telescope of
Abastumani Observatory (AbAO) on Dec. 28 (UT) 15:13:46 in R-filter. We
do not detected the afterglow (D'Avanzo et al., GCN 23575; Lipunov et
al. GCN 23576; Xu et al., GCN 23593).
Preliminary photometry of the field is following.
Date UT start t-T0 Filter Exp. OT Err. UL
(mid, days) (s)
2018-12-28 13:48:11 0.47494 I 30*120 n/d n/d 23.8
2018-12-28 15:13:46 0.54879 R 63*60 n/d n/d 21.0
The photometry is based on nearby USNO-B1.0 stars
USNO-B1.0_id R2 I2
1032-0046066 16.66 16.08
1031-0043284 16.04 15.36
GCN Circular 23594
Subject
GRB 181228A: Global MASTER Net OT is the same REM IR transient
Date
2018-12-31T09:57:40Z (7 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
V. Lipunov, N.Tiurina, E. Gorbovskoy, V.Kornilov, P.Balanutsa,
A.Kuznetsov, D. Vlasenko, D.Kobtsev
(Lomonosov Moscow State University, SAI),
R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix
Aguilar),
H. Levato
(Instituto de Ciencias Astronomicas, de la Tierra y del Espacio of San Juan
National University, Argentina)
R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres
(The Instituto de Astrofisica de Canarias),
D. Buckley (South African Astronomical Observatory),
A. Tlatov, V.Senik, D. Dormidontov
(Kislovodsk Solar Station of the Pulkovo Observatory),
O. Gress, N.M. Budnev, S. Yazev, O. Chuvalaev (Irkutsk State University, API)
V. Yurkov, A. Gabovich, Yu. Sergienko (Blagoveschensk Educational State
University)
The optical source detected by MASTER (Lipunov et al., GCN 23576) insidet
Swift BAT GRB 181228A error box (Moss et al., GCN 23570)
regardless of the infrared telescope REM (D'Avanzo et al., GCN 23575)
is one and the same source. The difference in coordinates is less than 3
sigma. Our coordinates are of course rather rough, since the source itself
is very weak. Let me remind you that the pixel MASTER is equal to 2.5
arcsec.
OT (not infrared) discovered by MASTER is disappear on late imeges!
HNY!
The message may be cited.
GCN Circular 23593
Subject
GRB 181228A: possible NOT optical detection
Date
2018-12-31T00:02:45Z (7 years ago)
From
Dong Xu at NAOC/CAS <dxu@nao.cas.cn>
D. Xu (NAOC), D.B. Malesani (DAWN/NBI/DTU and DARK/NBI), J.P.U. Fynbo
(DAWN/NBI and DAWN/DTU), M.I. Andersen (NBI), T. Pursimo (NOT) report:
We observed the field of GRB 181228A (Moss et al., GCN 23570) using the
2.56m Nordic Optical Telescope (NOT) equipped with ALFOSC, starting at
23:56:20 UT on 2018-12-28, i.e., 21.05 hr after the BAT trigger. We
obtained 3x300s unfiltered frames and 3x300s frames in the Sloan i-band.
There is a weak detection in our stacked image at the REM position
(D'Avanzo et al., GCN 23575), thus also being consistent with the
enhanced XRT error circle (Beardmore et al., GCN 23574). The above
position is not consistent with that of MASTER OT reported in Lipunov et
al. (GCN 23576). The NOT source has m(i)~25.0+/-0.5, calibrated with
nearby PanSTARRS stars, and thus it could be the optical counterpart of
GRB 181228A.
GCN Circular 23590
Subject
GRB 181228A: MITSuME Akeno optical upper limits
Date
2018-12-30T12:22:33Z (7 years ago)
From
Katsuhiro L. Murata at Nagoya U <murata@u.phys.nagoya-u.ac.jp>
M. Oeda, K. L. Murata, R. Itoh, Y. Tachibana, S. Harita, K. Morita, K.
Shiraishi, K. Iida, M. Niwano, R. Adachi, Y. Yatsu, and N. Kawai (Tokyo
Tech)
report on behalf of the MITSuME collaboration:
We searched for the optical counterpart of GRB 181228A (M. J. Moss et al.,
GCN Circular #23570) 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 09:04:35.19 UT. We did not find any new point
source within the enhanced XRT circle (A.P. Beardmore et al., GCN Circular
#23574) in all three bands. We obtained following limits for the magnitudes.
T0+[hour] MID-UT T-EXP[sec] g' Rc Ic
-------------------------------------------------------------------------------------------------------
6.188 13:04:51 25320 >19.1 >19.0 >18.6
-------------------------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time
We used UCAC-4 catalog for flux calibration.
GCN Circular 23588
Subject
GRB 181228A: Xinglong-2.16m optical upper limit
Date
2018-12-29T13:31:29Z (7 years ago)
From
Dong Xu at NAOC/CAS <dxu@nao.cas.cn>
Z.P. Zhu, L.P. Xin, D. Xu, J.B. Zhang (NAOC), X. Zhang, J.H. Liu (XAO)
report:
We observed the field of GRB 181228A (Moss et al., GCN 23570) using the
2.16-m telescope located at Xinglong, Hebei, China, equipped with the
BFOSC camera. We obtained 6x300s and 2x600s frames in I-band, starting
at 13:04:00 UT on 2018-12-28, i.e., 10.18 hrs after the BAT trigger.
The afterglow of GRB 181228A (e.g., Moss et al., GCN 23570; D'Avanzo et
al., GCN 23575; Lipunov et al., GCN 23576) is not detected in our
stacked image, down to a limiting magnitude of ~20.5 mag, calibrated
with the nearby PanSTARRS field.
GCN Circular 23584
Subject
GRB 181228A: Swift-XRT refined Analysis
Date
2018-12-28T20:51:37Z (7 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
S. J. LaPorte (PSU), J.A. Kennea (PSU), B. Sbarufatti (INAF-OAB/PSU),
A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), J.P. Osborne
(U. Leicester), A. D'Ai (INAF-IASFPA), A. Melandri (INAF-OAB), P.
D'Avanzo (INAF-OAB) and M.J. Moss report on behalf of the Swift-XRT
team:
We have analysed 6.2 ks of XRT data for GRB 181228A (Moss et al. GCN
Circ. 23570), from 88 s to 58.6 ks after the BAT trigger. The data
comprise 405 s in Windowed Timing (WT) mode with the remainder in
Photon Counting (PC) mode. The enhanced XRT position for this burst was
given by Beardmore et al. (GCN Circ. 23574).
The late-time light curve (from T0+12.9 ks) can be modelled with a
power-law decay with a decay index of alpha=0.95 (+0.29, -0.28).
A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.60 (+/-0.05). The
best-fitting absorption column is 3.30 (+0.28, -0.27) x 10^21 cm^-2,
in excess of the Galactic value of 2.9 x 10^21 cm^-2 (Willingale et al.
2013). The PC mode spectrum has a photon index of 1.80 (+0.20, -0.19)
and a best-fitting absorption column of 5.3 (+1.4, -1.2) x 10^21 cm^-2.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum is 4.6 x 10^-11 (6.8 x 10^-11) erg cm^-2
count^-1.
A summary of the PC-mode spectrum is thus:
Total column: 5.3 (+1.4, -1.2) x 10^21 cm^-2
Galactic foreground: 2.9 x 10^21 cm^-2
Excess significance: 3.2 sigma
Photon index: 1.80 (+0.20, -0.19)
If the light curve continues to decay with a power-law decay index of
0.95, the count rate at T+24 hours will be 0.012 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 5.7 x
10^-13 (8.4 x 10^-13) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00879909.
This circular is an official product of the Swift-XRT team.
GCN Circular 23583
Subject
GRB 181228A: Swift-BAT refined analysis
Date
2018-12-28T18:56:14Z (7 years ago)
From
Amy Lien at GSFC <amy.y.lien@nasa.gov>
A. Y. Lien (GSFC/UMBC), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), H. A. Krimm (NSF/USRA),
C. B. Markwardt (GSFC), M. J. Moss (GWU),
D. M. Palmer (LANL), T. Sakamoto (AGU),
M. Stamatikos (OSU), T. N. Ukwatta (LANL)
(i.e. the Swift-BAT team):
Using the data set from T-240 to T+962 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 181228A (trigger #879909)
(Moss et al., GCN Circ. 23570