TITLE: GCN CIRCULAR NUMBER: 25243 SUBJECT: Fermi trigger No 586305505 Global MASTER-Net observations report DATE: 19/07/31 23:31:09 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 (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-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB190731.94 (trigger No 586305505, 1h 4m 48.00s , -82d 39m 36.00s, R=1) errorbox 82 sec after notice time and 111 sec after trigger time at 2019-07-31 22:40:11 UT, with upper limit up to 17.9 mag. The observations began at zenit distance = 56 deg. The sun altitude is -76.2 deg. The galactic latitude b = -60 deg., longitude l = 98 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1093014 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 121 | 2019-07-31 22:40:11 | MASTER-SAAO | ( 1h 8m 35.77s , -82d 48m 30.23s) | P\ | 20 | 16.3 | 156 | 2019-07-31 22:40:11 | MASTER-SAAO | ( 1h 8m 36.13s , -82d 48m 30.40s) | P\ | 90 | 17.3 | Coadd 175 | 2019-07-31 22:41:00 | MASTER-SAAO | ( 1h 7m 06.35s , -82d 48m 30.90s) | P\ | 30 | 16.5 | 240 | 2019-07-31 22:42:00 | MASTER-SAAO | ( 1h 7m 07.70s , -82d 48m 30.76s) | P\ | 40 | 16.7 | 318 | 2019-07-31 22:43:08 | MASTER-SAAO | ( 1h 7m 09.25s , -82d 48m 30.62s) | P\ | 60 | 17.2 | 408 | 2019-07-31 22:43:08 | MASTER-SAAO | ( 1h 7m 09.27s , -82d 48m 30.62s) | P\ | 240 | 17.9 | Coadd 417 | 2019-07-31 22:44:36 | MASTER-SAAO | ( 1h 7m 11.07s , -82d 48m 30.40s) | P\ | 80 | 17.4 | The observation and reduction will continue. The message may be cited.