TITLE: GCN CIRCULAR NUMBER: 37223 SUBJECT: Fermi trigger No 745866488: Global MASTER-Net observations report DATE: 24/08/21 21:16:45 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko, G.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij (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. Gress, N.M. Budnev, O.Ershova (Irkutsk State University, API), L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), V. Yurkov, A. Gabovich (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 GRB240820.71 (trigger No 745866488,14h 28m 28.08s , +09d 51m 00.0s, R=32.13) errorbox 1802 sec after notice time and 1838 sec after trigger time at 2024-08-20 17:38:41 UT, with upper limit up to 17.9 mag. Observations started at twilight. The observations began at zenith distance = 51 deg. The sun altitude is -10.7 deg. The galactic latitude b = 61 deg., longitude l = 1 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2569425 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 1868 | 2024-08-20 17:38:41 | MASTER-Tavrida | (13h 14m 26.98s , +38d 41m 43.3s) | C | 60 | 16.7 | 1868 | 2024-08-20 17:38:42 | MASTER-Tavrida | (13h 14m 35.07s , +38d 36m 45.2s) | C | 60 | 17.0 | 1943 | 2024-08-20 17:39:57 | MASTER-Tavrida | (13h 24m 39.89s , +38d 42m 32.4s) | C | 60 | 17.0 | 1943 | 2024-08-20 17:39:57 | MASTER-Tavrida | (13h 24m 48.04s , +38d 37m 36.9s) | C | 60 | 17.1 | 2018 | 2024-08-20 17:41:11 | MASTER-Tavrida | (13h 15m 55.45s , +39d 53m 36.8s) | C | 60 | 17.2 | 2094 | 2024-08-20 17:42:27 | MASTER-Tavrida | (13h 26m 19.05s , +39d 58m 35.6s) | C | 60 | 17.3 | 2094 | 2024-08-20 17:42:27 | MASTER-Tavrida | (13h 26m 27.45s , +39d 53m 40.1s) | C | 60 | 17.4 | 2168 | 2024-08-20 17:43:42 | MASTER-Tavrida | (13h 14m 29.34s , +38d 42m 07.1s) | C | 60 | 17.2 | 2168 | 2024-08-20 17:43:42 | MASTER-Tavrida | (13h 14m 37.72s , +38d 37m 11.9s) | C | 60 | 17.3 | 2244 | 2024-08-20 17:44:57 | MASTER-Tavrida | (13h 24m 44.13s , +38d 40m 34.1s) | C | 60 | 17.4 | 2244 | 2024-08-20 17:44:57 | MASTER-Tavrida | (13h 24m 52.47s , +38d 35m 39.3s) | C | 60 | 17.5 | 2319 | 2024-08-20 17:46:13 | MASTER-Tavrida | (13h 16m 01.00s , +39d 55m 27.5s) | C | 60 | 17.5 | 2394 | 2024-08-20 17:47:28 | MASTER-Tavrida | (13h 26m 14.12s , +39d 59m 15.7s) | C | 60 | 17.5 | 2394 | 2024-08-20 17:47:28 | MASTER-Tavrida | (13h 26m 22.63s , +39d 54m 21.3s) | C | 60 | 17.9 | 2469 | 2024-08-20 17:48:43 | MASTER-Tavrida | (13h 14m 27.60s , +38d 42m 23.1s) | C | 60 | 17.4 | 2469 | 2024-08-20 17:48:43 | MASTER-Tavrida | (13h 14m 36.05s , +38d 37m 27.8s) | C | 60 | 17.5 | 2544 | 2024-08-20 17:49:57 | MASTER-Tavrida | (13h 24m 48.58s , +38d 41m 15.5s) | C | 60 | 17.7 | 2544 | 2024-08-20 17:49:58 | MASTER-Tavrida | (13h 24m 56.95s , +38d 36m 20.4s) | C | 60 | 17.6 | 2695 | 2024-08-20 17:52:29 | MASTER-Tavrida | (13h 15m 59.17s , +39d 54m 57.6s) | C | 60 | 17.7 | 2844 | 2024-08-20 17:54:58 | MASTER-Tavrida | (13h 26m 20.76s , +39d 59m 45.9s) | C | 60 | 17.8 | 2844 | 2024-08-20 17:54:58 | MASTER-Tavrida | (13h 26m 29.21s , +39d 54m 51.2s) | C | 60 | 17.9 | 99564 | 2024-08-21 20:45:57 | MASTER-Tavrida | (15h 15m 49.43s , +19d 07m 42.0s) | C | 180 | 14.7 | 99747 | 2024-08-21 20:49:00 | MASTER-Tavrida | (15h 15m 51.12s , +19d 07m 39.1s) | C | 180 | 14.6 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.