TITLE: GCN CIRCULAR NUMBER: 28256 SUBJECT: Fermi GRB 200817A: Global MASTER-Net observations report DATE: 20/08/17 14:00:19 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva, D.Kuvshinov, D. Cheryasov (Lomonosov Moscow State University, SAI, Physics Department), R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA), H.Levato (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE), R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), O.A. Gres, N.M. Budnev, O.Ershova (Irkutsk State University, API), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), V. Yurkov, A. Gabovich, Yu. Sergienko (Blagoveschensk Educational State University) MASTER-Tunka robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Applied Physics Institute, Irkutsk State University) started inspect of the Fermi GRB 200817A ( Fermi GBM team, GCN 28254) errorbox 14716 sec after notice time and 14749 sec after trigger time at 2020-08-17 13:31:09 UT, with upper limit up to 18.3 mag. Observations started at twilight. The observations began at zenith distance = 43 deg. The sun altitude is -10.0 deg. The galactic latitude b = 66 deg., longitude l = 120 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1421422 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 14780 | 2020-08-17 13:31:09 | MASTER-Tunka | (12h 57m 56.42s , +58d 23m 36.8s) | C | 60 | 16.9 | 14859 | 2020-08-17 13:32:29 | MASTER-Tunka | (13h 14m 28.63s , +56d 23m 12.7s) | C | 60 | 17.1 | 14939 | 2020-08-17 13:33:49 | MASTER-Tunka | (12h 45m 43.50s , +56d 22m 38.3s) | C | 60 | 17.2 | 15018 | 2020-08-17 13:35:08 | MASTER-Tunka | (13h 02m 54.40s , +54d 23m 36.1s) | C | 60 | 17.4 | 15098 | 2020-08-17 13:36:27 | MASTER-Tunka | (12h 57m 48.21s , +58d 24m 27.1s) | C | 60 | 17.3 | 15177 | 2020-08-17 13:37:47 | MASTER-Tunka | (13h 13m 04.06s , +58d 23m 38.4s) | C | 60 | 17.5 | 15257 | 2020-08-17 13:39:07 | MASTER-Tunka | (13h 14m 22.85s , +56d 22m 39.2s) | C | 60 | 17.7 | 15337 | 2020-08-17 13:40:26 | MASTER-Tunka | (13h 28m 48.70s , +56d 22m 54.9s) | C | 60 | 17.7 | 15416 | 2020-08-17 13:41:46 | MASTER-Tunka | (12h 45m 42.90s , +56d 23m 42.2s) | C | 60 | 17.7 | 15496 | 2020-08-17 13:43:06 | MASTER-Tunka | (13h 00m 03.48s , +56d 22m 46.0s) | C | 60 | 17.8 | 15577 | 2020-08-17 13:44:27 | MASTER-Tunka | (13h 03m 00.68s , +54d 24m 04.9s) | C | 60 | 18.0 | 15657 | 2020-08-17 13:45:47 | MASTER-Tunka | (13h 16m 32.39s , +54d 23m 33.9s) | C | 60 | 18.2 | 15737 | 2020-08-17 13:47:06 | MASTER-Tunka | (13h 12m 57.57s , +58d 24m 26.9s) | C | 60 | 18.1 | 15816 | 2020-08-17 13:48:26 | MASTER-Tunka | (13h 28m 47.54s , +56d 23m 39.4s) | C | 60 | 18.1 | 15895 | 2020-08-17 13:49:45 | MASTER-Tunka | (12h 59m 59.01s , +56d 22m 13.0s) | C | 60 | 18.2 | 15975 | 2020-08-17 13:51:05 | MASTER-Tunka | (13h 16m 37.84s , +54d 22m 52.0s) | C | 60 | 18.3 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.