GCN Circular 19914
Subject
GRB 160910A: Global MASTER Net OT detection before LAT alert
Date
2016-09-12T19:16:03Z (8 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
V. Lipunov, E. Gorbovskoy, N.Tyurina, V.Kornilov,
P.Balanutsa, A.Kuznetsov, D.Kuvshinov
Lomonosov Moscow State University, Sternberg Astronomical Institute
D.Buckley, S. Potter, A.Kniazev, M.Kotze
South African Astronomical Observatory
R. Rebolo, M. Serra Ricart, N. Lodieu, G. Israelian
The Instituto de Astrofisica de Canarias
K.Ivanov, O.Gres, N.M.Budnev, S.Yazev,
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
Hugo Levato, Carlos Saffe
Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)
R.Podesta, C.Lopez, F. Podesta
Observatorio Astronomico Felix Aguilar (OAFA)
MASTER-SAAO robotic telescope (MASTER-Net: http://observ.pereplet.ru)
located in SAAO was pointed to the FERMI GBM GRB160910.72 15 sec after
notice time and 65 sec after trigger time at 2016-09-10 17:20:45 UT.
On our first (20s exposure started 75 sec after GBM trigger) set we do
not found optical transient within FERMI error-box (ra=14 54 00
dec=+39 23 00 r=3.41, trigger 495220783 / 160910722
(Veres and C.Meegan, GCN 19901)) because very low
altitude on horizont ~3 degrees (one tube was under the roof).
Fortunatelly, we saw OT by one of two MASTER Very Wide Field Cameras (5
sec expositon, 0.25 sec readout) .
On MASTER-SAAO VWF Camera we see OT at 3 sigma confidence level with
magnitude 11.6 +- 0.5 mag on a co-added images with total exposure 95
seconds (19 x 5 sec) starting at 17:20:45 i.e. 65 sec after trigger time. Mean
time is 113 sec after trigger.
On our second MASTER-SAAO (30s
exposure) set started at 2016-09-10 17:22:26 (167 sec after trigger time)
we found OT within FERMI error-box with unfileterd
magnitide m = 11.6+-0.1 . The second exposition was making after receiving
new Fermi GBM coordinates.
Ra, Dec = 14h 45m 46.03s +39d 04m 00.52s
err = +-0.5 arcsec
(cf. A. D'A. et al., GCN 19904; A. de Ugarte Postigo et al., 19907;
Malesani et al., GCN 19908 )
MASTER-IAC robotic telescope (MASTER-Net: http://observ.pereplet.ru)
located in IAC was starting survey on the FERMI GBM GRB160910.72
error-box (ra=14 46 14 dec=+39 25 10 r=1.0) 11142 sec after notice time
and 11239 sec after trigger time at 2016-09-10 20:26:58 UT. The 5-sigma upper
limit on our first (60s exposure) set is about 18.3 mag . The OT
unfiltered magnitude is 17.4+-0.4 .
The light curve is available at
http://master.sai.msu.ru/static/GRB160910A.png
The MASTER-SAAO power law index alpha = 1.30+-0.07 ( I ~ t^-alpha) in
agreement with MASTER-IAC and some
contradiction with late point (Malesani et al., GCN 19908 )
The MASTER-SAAO and NOT combined power law index alpha =
1.17+-0.02 .
All MASTER observations was done before LAT alert.
The message may be cited.
