[vsnet-grb-info 16973] GRB 150907B: MASTER-SAAO early optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18254
SUBJECT: GRB 150907B: MASTER-SAAO early optical observations 
DATE:    15/09/08 08:22:48 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov at xray.sai.msu.ru>

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

V. Lipunov, E.Gorbovskoy,  N.Tyurina, V.Kornilov, P.Balanutsa, 
A.Kuznetsov, D.Kuvshinov, I.Gorbunov
Lomonosov Moscow State University, Sternberg Astronomical Institute

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

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

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

V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov, A.Gabovich
Blagoveschensk Educational State University, Blagoveschensk

V.Krushinski, I.Zalozhnih
Ural Federal University, Kourovka

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

Carlos Lopez, Claudio Mallamaci and Federico Podest
Observatorio Astronomico Felix Aguilar (OAFA)



MASTER II  robotic telescope (MASTER-Net: http://observ.pereplet.ru) 
located in SAAO was pointed to the Swift Alert (Roegiers et al., GCN 
18249) GRB150907B 25 sec after notice time 
and 40 sec after trigger time at 2015-09-07 23:27:10 UT. On our first (10s 
exposure)  set we haven`t found optical transient  within SWIFT error-box 
(ra=17 00 51 dec=-63 49 07 r=0.050000).
The next images limit without OT:

  Id     	Coord             Pro.type Time,UT Exp.time  Lim Filt. Tube

110113	16h 59m 04.1s -63d 41m 01s  Alert  23:27:10  10	    15.5  P  EAST
110114	17h 00m 00.1s -63d 42m 55s  Alert  23:27:10  10     15.7  P  WEST
110115	16h 59m 47.7s -63d 42m 57s  Alert  23:27:34  10     15.4  P  WEST
110116	16h 59m 22.0s -63d 41m 10s  Alert  23:27:34  10     15.2  P  EAST
110117	16h 59m 47.5s -63d 42m 57s  Alert  23:27:56  20	    15.9  P  WEST
110118	16h 59m 21.8s -63d 41m 10s  Alert  23:27:56  20	    15.7  P  EAST
110119	16h 59m 21.6s -63d 41m 09s  Alert  23:28:27  20	    15.9  P  EAST
110120	16h 59m 47.4s -63d 42m 56s  Alert  23:28:27  20	    16.1  P  WEST
110121	16h 59m 21.6s -63d 41m 09s  Alert  23:28:58  30	    13.2  P  EAST
110122	16h 59m 47.4s -63d 42m 56s  Alert  23:28:58  30     13.5  P  WEST
110123	17h 00m 00.1s -63d 42m 55s SumAlert23:27:10  40	    16.3  P  WEST
110124	16h 59m 21.4s -63d 41m 08s  Alert  23:29:39  40	    15.1  P  EAST
110125	16h 59m 47.1s -63d 42m 55s  Alert  23:29:39  40	    15.5  P  WEST
110126	16h 59m 04.1s -63d 41m 01s SumAlert23:27:10  40	    16.1  P  EAST
110127	16h 59m 47.1s -63d 42m 55s  Alert  23:30:30  50	    15.9  P  WEST
110128	16h 59m 21.3s -63d 41m 08s  Alert  23:30:30  50	    15.5  P  EAST
110129	16h 59m 47.4s -63d 42m 56s SumAlert23:28:27  90     15.9  P  WEST
110130	16h 59m 21.2s -63d 41m 08s  Alert  23:31:31  60	    14.8  P  EAST
110131	16h 59m 47.1s -63d 42m 56s  Alert  23:31:31  60	    15.4  P  WEST
110132	16h 59m 21.6s -63d 41m 09s SumAlert23:28:27  110    16.1  P  EAST

There was a short time between rain and clouds. Then the clouds returned.

The message may be cited.