TITLE: GCN CIRCULAR NUMBER: 30123 SUBJECT: Fermi trigger No 644449593: Global MASTER-Net observations report DATE: 21/06/04 00:15:20 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-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 GRB210603.91 (trigger No 644449593,09h 43m 31.20s , -62d 07m 12.0s, R=9.84) errorbox 5893 sec after notice time and 5923 sec after trigger time at 2021-06-03 23:25:11 UT, with upper limit up to 18.2 mag. The observations began at zenith distance = 38 deg. The sun altitude is -22.0 deg. The galactic latitude b = -7 deg., longitude l = 283 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1627784 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 5953 | 2021-06-03 23:25:11 | MASTER-OAFA | (09h 23m 43.99s , -62d 06m 42.3s) | C | 60 | 18.0 | 6032 | 2021-06-03 23:26:30 | MASTER-OAFA | (09h 40m 23.74s , -62d 04m 31.7s) | C | 60 | 17.8 | 6112 | 2021-06-03 23:27:50 | MASTER-OAFA | (09h 26m 56.30s , -63d 58m 59.2s) | C | 60 | 18.1 | 6192 | 2021-06-03 23:29:09 | MASTER-OAFA | (09h 44m 37.83s , -63d 59m 26.1s) | C | 60 | 18.0 | 6271 | 2021-06-03 23:30:29 | MASTER-OAFA | (09h 55m 29.06s , -62d 05m 15.0s) | C | 60 | 17.5 | 6350 | 2021-06-03 23:31:48 | MASTER-OAFA | (10h 12m 04.95s , -62d 05m 58.3s) | C | 60 | 17.2 | 6430 | 2021-06-03 23:33:08 | MASTER-OAFA | (09h 31m 12.04s , -65d 52m 50.9s) | C | 60 | 18.0 | 6509 | 2021-06-03 23:34:27 | MASTER-OAFA | (09h 50m 15.63s , -65d 53m 59.5s) | C | 60 | 17.9 | 6589 | 2021-06-03 23:35:47 | MASTER-OAFA | (09h 21m 20.78s , -60d 12m 03.8s) | C | 60 | 17.9 | 6668 | 2021-06-03 23:37:06 | MASTER-OAFA | (09h 37m 06.39s , -60d 10m 43.0s) | C | 60 | 17.9 | 6748 | 2021-06-03 23:38:26 | MASTER-OAFA | (10h 00m 37.27s , -64d 00m 15.7s) | C | 60 | 17.7 | 6828 | 2021-06-03 23:39:46 | MASTER-OAFA | (10h 18m 31.76s , -63d 59m 34.3s) | C | 60 | 17.6 | 6907 | 2021-06-03 23:41:05 | MASTER-OAFA | (09h 23m 39.26s , -62d 05m 15.9s) | C | 60 | 18.0 | 6987 | 2021-06-03 23:42:25 | MASTER-OAFA | (09h 40m 22.14s , -62d 06m 37.4s) | C | 60 | 17.8 | 7066 | 2021-06-03 23:43:44 | MASTER-OAFA | (09h 26m 54.13s , -63d 59m 24.8s) | C | 60 | 18.1 | 7146 | 2021-06-03 23:45:04 | MASTER-OAFA | (09h 44m 36.01s , -63d 59m 35.5s) | C | 60 | 18.0 | 7225 | 2021-06-03 23:46:23 | MASTER-OAFA | (09h 55m 20.26s , -62d 04m 23.7s) | C | 60 | 17.6 | 7307 | 2021-06-03 23:47:45 | MASTER-OAFA | (10h 12m 09.80s , -62d 05m 06.2s) | C | 60 | 17.2 | 7386 | 2021-06-03 23:49:04 | MASTER-OAFA | (09h 31m 08.56s , -65d 54m 52.1s) | C | 60 | 18.2 | 7466 | 2021-06-03 23:50:24 | MASTER-OAFA | (09h 50m 17.99s , -65d 54m 00.8s) | C | 60 | 18.0 | 7545 | 2021-06-03 23:51:43 | MASTER-OAFA | (09h 21m 23.68s , -60d 11m 26.4s) | C | 60 | 17.9 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.