[vsnet-grb-info 26356] GRB 200916B: MASTER optical observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  28456
SUBJECT: GRB 200916B: MASTER optical observation
DATE:    20/09/19 12:27:13 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov at xray.sai.msu.ru>

V. Lipunov, V.Kornilov, E.Gorbovskoy, N.Tiurina, P.Balanutsa, A.Kuznetsov, K.Zhirkov, F.Balakin,
V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, A.Chasovnikov, V.Topolev, 
A.Pozdnyakov, D.Cheryasov(Lomonosov Moscow State University, SAI, Physics Department),
R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA),
R. Rebolo, M. Serra(The Instituto de Astrofisica de Canarias),
D. Buckley (South African Astronomical Observatory),
O.A. Gres, N.M. Budnev (Irkutsk State University, API),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
A. Gabovich, V.Yurkov, Yu. Sergienko (Blagoveschensk Educational State University)


MASTER-SAAO robotic telescope
(Global MASTER-Net http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, 2010, 30L)
located in South Africa (South African Astronomical Observatory)
started inspect of short GRB200916B (Ridnaia et al. GCN 28440) errorbox 
85399s after notice time (2 days 6634s after trigger time) at 2020-09-18 17:32:03 UT,
with upper limit  to  19.4 mag.
The observations began at zenith distance = 45 deg. The sun altitude was -13.4 deg.
The galactic latitude b = -60 deg., longitude l = 98 deg.

Real time updated cover map:
https://master.sai.msu.ru/site/master2/ligo_1.php?id=11529

We obtained following upper limits.

Tmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment
   179525 | 2020-09-18 17:32:03 |         MASTER-SAAO | (15h 02m 46.17s , -37d 57m 43.2s) |   C |   180 | 19.4 |
   180925 | 2020-09-18 17:55:23 |         MASTER-SAAO | (14h 49m 20.69s , -39d 56m 18.2s) |   C |   180 | 19.3 |
   181124 | 2020-09-18 17:58:43 |         MASTER-SAAO | (14h 49m 16.07s , -39d 57m 17.9s) |   C |   180 | 19.3 |
Filter C is a clear (unfiltred) band.

The observation and reduction will continue.
The message may be cited.