TITLE: GCN CIRCULAR NUMBER: 30795 SUBJECT: Fermi trigger No 652934203: Global MASTER-Net observations report DATE: 21/09/10 07:31:02 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru> 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-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 GRB210910.11 (trigger No 652934203,19h 14m 28.80s , +25d 57m 36.0s, R=16.78) errorbox 3 sec after trigger time at 2021-09-10 02:36:41 UT, with upper limit up to 17.5 mag. The observations began at zenith distance = 72 deg. The sun altitude is -52.5 deg. The galactic latitude b = 6 deg., longitude l = 59 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1715870 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 33 | 2021-09-10 02:36:41 | MASTER-OAFA | (19h 29m 08.82s , +36d 32m 41.8s) | C | 60 | 17.5 | 113 | 2021-09-10 02:38:01 | MASTER-OAFA | (19h 49m 25.16s , +30d 52m 15.4s) | C | 60 | 16.6 | 192 | 2021-09-10 02:39:20 | MASTER-OAFA | (19h 58m 48.36s , +30d 50m 33.4s) | C | 60 | 16.9 | 272 | 2021-09-10 02:40:40 | MASTER-OAFA | (19h 47m 24.95s , +13d 46m 00.4s) | C | 60 | 17.4 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.