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GCN Circular 25948

Swift GRB191004.9: Global MASTER-Net OT detection
2019-10-04T21:44:00Z (5 years ago)
Vladimir Lipunov at Moscow State U/Krylov Obs <>
V. Lipunov, E. Gorbovskoy, V.Kornilov, D.Kuvshinov, N.Tyurina, 
A.Kuznetsov, D. Vlasenko, F. Balakin
Lomonosov Moscow State University,
Sternberg Astronomical Institute, Moscow State University

D. Buckley, S. Potter, A. Kniazev, M. Kotze
South African Astronomical Observatory

K. Ivanov, O. Gres, N.M. Budnev, S. Yazev, O. Chuvalaev, V. Poleshchuk
Irkutsk State University

A. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov
Kislovodsk Solar Station of the Pulkovo Observatory

V. Yurkov, A. Gabovich, Yu. Sergienko
Blagoveschensk Educational State University, Blagoveschensk

R. Podesta, Carlos Lopez and F. Podesta
Observatorio Astronomico Felix Aguilar (OAFA)

Hugo Levato
Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)

R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres
The Instituto de Astrofisica de Canarias

MASTER-SAAO robotic telescope (Global MASTER-Net:, Lipunov et al., 2010, Advances in Astronomy, 
vol. 2010, 30L) located in South Africa (South African Astronomical 
Observatory) was pointed to the  GRB191004.9 23 sec after notice time and 
40 sec after trigger time at 2019-10-04 21:34:21 UT. On our first (10s 
exposure)  set we  found 1 optical transient within Swift error-box 
(ra=49.175 dec=-39.6125 r=0.05) brighter than 16.75.

  T-Tmid      Date      Time       Expt.        Ra                Dec 
       45   2019-10-04 21:34:21      10   (03h 16m 49.143s , -39d 38m 03.93s)    15.63

The 5-sigma upper limit has been about 16.75mag
The message may be cited.


The galactic latitude b = -57 deg., longitude l = 244 deg.
The observations made on zenit distance = 42 deg.The moon (42 % bright 
part) is 15 deg. above the horizon. The distance between  moon and  object 
is 106
The sun  altitude  is -51.4 deg.
The object can be observed till sunrise at 2019-10-05 04:09:28
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