TITLE: GCN CIRCULAR NUMBER: 30819 SUBJECT: Fermi trigger No 653093506: Global MASTER-Net observations report DATE: 21/09/11 23:30:16 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), 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-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) started inspect of the Fermi GRB210911.95 (trigger No 653093506,19h 23m 33.60s , +21d 45m 36.0s, R=18.94) errorbox 165 sec after notice time and 208 sec after trigger time at 2021-09-11 22:55:10 UT, with upper limit up to 17.6 mag. The observations began at zenith distance = 68 deg. The sun altitude is -38.8 deg. The galactic latitude b = 3 deg., longitude l = 56 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1718035 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 238 | 2021-09-11 22:55:10 | MASTER-Tavrida | (19h 42m 50.23s , +14d 10m 49.8s) | C | 60 | 15.6 | 469 | 2021-09-11 22:59:00 | MASTER-Tavrida | (20h 14m 14.24s , +14d 10m 48.6s) | C | 60 | 17.0 | 548 | 2021-09-11 23:00:19 | MASTER-Tavrida | (20h 21m 45.86s , +14d 09m 48.0s) | C | 60 | 17.1 | 627 | 2021-09-11 23:01:38 | MASTER-Tavrida | (20h 29m 54.86s , +14d 08m 48.2s) | C | 60 | 17.3 | 706 | 2021-09-11 23:02:57 | MASTER-Tavrida | (20h 11m 03.14s , +21d 45m 15.2s) | C | 60 | 16.3 | 785 | 2021-09-11 23:04:16 | MASTER-Tavrida | (20h 19m 37.72s , +21d 46m 28.6s) | C | 60 | 16.0 | 1023 | 2021-09-11 23:08:14 | MASTER-Tavrida | (19h 34m 34.30s , +14d 10m 22.6s) | C | 60 | 15.3 | 1102 | 2021-09-11 23:09:33 | MASTER-Tavrida | (19h 50m 16.16s , +14d 08m 15.3s) | C | 60 | 16.4 | 1181 | 2021-09-11 23:10:52 | MASTER-Tavrida | (19h 58m 38.40s , +14d 08m 19.1s) | C | 60 | 16.9 | 1261 | 2021-09-11 23:12:12 | MASTER-Tavrida | (19h 42m 53.12s , +14d 09m 45.2s) | C | 60 | 16.1 | 1699 | 2021-09-11 23:19:30 | MASTER-Tavrida | (20h 36m 24.65s , +19d 52m 31.4s) | C | 60 | 17.6 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.