TITLE: GCN CIRCULAR NUMBER: 28243 SUBJECT: Fermi GRB 200809B: Global MASTER-Net observations report DATE: 20/08/10 17:15:10 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-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB 200809B ( Fermi GBM team, GCN 28236) errorbox 27196 sec after notice time and 27226 sec after trigger time at 2020-08-09 23:15:13 UT, with upper limit up to 18.3 mag. Observations started at twilight. The observations began at zenith distance = 71 deg. The sun altitude is -15.3 deg. MASTER-SAAO robotic telescope located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB 200809B errorbox 1 days 4224 sec after notice time and 1 days 4253 sec after trigger time at 2020-08-10 16:52:21 UT, with upper limit up to 17.9 mag. Observations started at twilight. The observations began at zenith distance = 65 deg. The sun altitude is -9.8 deg. The galactic latitude b = -40 deg., longitude l = 307 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1416521 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 27316 | 2020-08-09 23:15:13 | MASTER-OAFA | (01h 02m 46.23s , -74d 39m 11.1s) | C | 180 | 18.0 | 27749 | 2020-08-09 23:22:26 | MASTER-OAFA | (01h 02m 47.91s , -74d 41m 22.8s) | C | 180 | 18.1 | 28173 | 2020-08-09 23:29:29 | MASTER-OAFA | (01h 02m 50.85s , -74d 39m 24.3s) | C | 180 | 18.2 | 28598 | 2020-08-09 23:36:34 | MASTER-OAFA | (01h 02m 54.25s , -74d 39m 46.9s) | C | 180 | 18.2 | 29023 | 2020-08-09 23:43:40 | MASTER-OAFA | (01h 02m 49.90s , -74d 39m 21.1s) | C | 180 | 18.0 | 29448 | 2020-08-09 23:50:44 | MASTER-OAFA | (01h 02m 50.04s , -74d 41m 20.6s) | C | 180 | 18.0 | 31197 | 2020-08-10 00:19:53 | MASTER-OAFA | (01h 02m 59.48s , -74d 39m 21.9s) | C | 180 | 18.3 | 31618 | 2020-08-10 00:26:55 | MASTER-OAFA | (01h 02m 53.37s , -74d 39m 10.0s) | C | 180 | 18.3 | 57541 | 2020-08-10 07:38:58 | MASTER-OAFA | (01h 02m 58.89s , -74d 41m 01.4s) | C | 180 | 16.8 | 57741 | 2020-08-10 07:42:17 | MASTER-OAFA | (01h 02m 56.20s , -74d 39m 38.4s) | C | 180 | 17.1 | 57940 | 2020-08-10 07:45:37 | MASTER-OAFA | (01h 02m 56.15s , -74d 41m 07.6s) | C | 180 | 17.4 | 58140 | 2020-08-10 07:48:57 | MASTER-OAFA | (01h 02m 59.81s , -74d 39m 27.4s) | C | 180 | 17.2 | 58340 | 2020-08-10 07:52:16 | MASTER-OAFA | (01h 02m 53.24s , -74d 40m 19.7s) | C | 180 | 16.6 | 58539 | 2020-08-10 07:55:36 | MASTER-OAFA | (01h 02m 53.57s , -74d 39m 21.4s) | C | 180 | 16.5 | 90684 | 2020-08-10 16:52:21 | MASTER-SAAO | (23h 43m 25.70s , -78d 04m 51.2s) | C | 60 | 17.5 | 90684 | 2020-08-10 16:52:21 | MASTER-SAAO | (00h 17m 44.42s , -78d 03m 55.8s) | C | 60 | 17.4 | 90763 | 2020-08-10 16:53:40 | MASTER-SAAO | (23h 43m 26.71s , -78d 04m 49.1s) | C | 60 | 17.6 | 90763 | 2020-08-10 16:53:40 | MASTER-SAAO | (00h 17m 45.09s , -78d 03m 53.9s) | C | 60 | 17.5 | 90843 | 2020-08-10 16:55:00 | MASTER-SAAO | (23h 40m 17.20s , -80d 05m 50.2s) | C | 60 | 17.7 | 90843 | 2020-08-10 16:55:00 | MASTER-SAAO | (00h 21m 30.38s , -80d 04m 52.9s) | C | 60 | 17.6 | 90923 | 2020-08-10 16:56:20 | MASTER-SAAO | (00h 15m 05.09s , -76d 03m 10.0s) | C | 60 | 17.9 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.