TITLE: GCN CIRCULAR NUMBER: 28233 SUBJECT: Fermi trigger No 618642276: Global MASTER-Net observations report DATE: 20/08/09 05:30:07 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 GRB200809.21 (trigger No 618642276,15h 46m 40.08s , -42d 36m 00.0s, R=30.72) errorbox 284 sec after notice time and 312 sec after trigger time at 2020-08-09 05:09:43 UT, with upper limit up to 17.4 mag. The observations began at zenith distance = 64 deg. The sun altitude is -73.4 deg. The galactic latitude b = 9 deg., longitude l = 334 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1416263 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 342 | 2020-08-09 05:09:43 | MASTER-OAFA | (16h 23m 31.69s , -41d 13m 46.0s) | C | 60 | 17.3 | 421 | 2020-08-09 05:11:02 | MASTER-OAFA | (16h 11m 38.74s , -43d 15m 21.2s) | C | 60 | 17.3 | 501 | 2020-08-09 05:12:22 | MASTER-OAFA | (16h 15m 03.33s , -39d 13m 53.7s) | C | 60 | 17.4 | 580 | 2020-08-09 05:13:42 | MASTER-OAFA | (16h 02m 08.45s , -41d 13m 35.9s) | C | 60 | 17.1 | 660 | 2020-08-09 05:15:01 | MASTER-OAFA | (16h 23m 31.84s , -41d 14m 45.6s) | C | 60 | 17.3 | 739 | 2020-08-09 05:16:20 | MASTER-OAFA | (16h 34m 16.65s , -41d 14m 04.2s) | C | 60 | 17.2 | 819 | 2020-08-09 05:17:40 | MASTER-OAFA | (16h 11m 44.50s , -43d 14m 19.5s) | C | 60 | 17.3 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.