[vsnet-grb-info 10955] GRB 110921A: MASTER-Net early limit

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  12374
SUBJECT: GRB 110921A: MASTER-Net early limit
DATE:    11/09/21 15:00:27 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <gcncirc at observ.inetcomm.ru>

V.Yurkov, Yu.Sergienko, E.Sinyakov,  D.Varda, I.Kudelina
Blagoveschensk Educational State University, Blagoveschensk

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

E. Gorbovskoy, V. Lipunov, V.Kornilov, D.Kuvshinov, A.Belinski, 
N.Tyurina, N.Shatskiy, P.Balanutsa, V.V.Chazov, P.V.Kortunov, A.Kuznetsov, 
D.Zimnukhov, M. Kornilov, A.Sankovich
Sternberg Astronomical Institute, Moscow State University

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

V.Krushinski, I.Zalozhnich, T.Kopytova, A. Popov
Ural State University, Kourovka


  MASTER II  robotic telescopes (MASTER-Net: http://observ.pereplet.ru) 
located in Amur  and in Tunka (Siberia) was pointed to the  GRB110921A 7 
sec after notice time and 53 sec after GRB time at 2011-09-21 
13:52:13.432 UT. On our first (10s exposure) set we haven`t found optical  transient  within SWIFT error-box (ra=19 36 19 dec=+36 22 48 r=0.050000). 
Observations were made in polarizing bands.
The 5-sigma upper limit has been about 17.2 in Amur and 17.5 
in Tunka.
Observations and data reduction is  continued.
The message may be cited.