[vsnet-grb-info 18982] GRB 170121A/Fermi trigger 506702667 MASTER-Amur OT detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  20502
SUBJECT: GRB 170121A/Fermi trigger 506702667  MASTER-Amur OT detection 
DATE:    17/01/22 22:22:36 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov at xray.sai.msu.ru>

V. Lipunov, E. Gorbovskoy, E.Popova, N.Tyurina, V.Kornilov, 
D.Kuvshinov, N.Tyurina, A.V.Krylov, I.Gorbunov, P.Balanutsa,
A.Kuznetsov, V.V.Chazov, D.Vlasenko
Lomonosov Moscow State
University, Sternberg Astronomical Institut of MSU

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

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

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

R.Podesta, C.Lopez, F. Podesta Observatorio Astronomico Felix Aguilar (OAFA) , 
National University of San Juan, Argentina

H. Levato, C. Saffe
Instituto de Ciencias Astronomicas,de la Tierra y del Espacio (ICATE),
San Juan, Argentina

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

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


MASTER II  robotic telescope (MASTER-Net: http://observ.pereplet.ru) 
located in Blagoveschensk was pointed to the  Fermi trigger Number 
506702667  72 sec  after 
notice time and 171 sec after trigger time at 2017-01-21 14:47:14 UT.

MASTER-Amur auto-detection system discovered OT source at (RA, Dec) = 04h 
50m 17.73s -09d 16m 02.0s .
The OT unfiltered magnitude is 14.9m (limit 16.0 m).

The OT is seen in 5 images. OT detected before maximum and shown decay on 
last images  4 minutes after detection.

We have reference image without OT on 2017-01-21.61560 UT with unfiltered 
magnitude limit 20.5 m.

Spectral observations are required.

The message may be cited.