[vsnet-grb-info 23845] Swift GRB191004.75: Global MASTER-Net OT detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  25944
SUBJECT: Swift GRB191004.75: Global MASTER-Net OT detection
DATE:    19/10/04 18:26:11 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov at xray.sai.msu.ru>

V. Lipunov, E. Gorbovskoy, V.Kornilov, D.Kuvshinov, N.Tyurina, 
P.Balanutsa,
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: 
http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, 
vol. 2010, 30L) located in South Africa (South African Astronomical 
Observatory) was pointed to the  GRB191004.75 25 sec after notice time and 
43 sec after trigger time at 2019-10-04 18:07:45 UT. On our first (10s 
exposure)  set we  found 1 optical transient within Swift error-box 
(ra=31.7208 dec=-36.9319 r=0.05) brighter than 23.


  T-Tmid      Date      Time       Expt.        Ra                Dec 
Mag
---------|---------------------|-------|-----------------|-----------------|-------
       48   2019-10-04 18:07:45      10   (02h 06m 40.526s , -36d 56m 
00.41s)    15.11

The 5-sigma upper limit has been about 23mag
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