TITLE: GCN CIRCULAR NUMBER: 24929 SUBJECT: Swift GRB190631. Global MASTER-Net observations report DATE: 19/07/01 00:55:20 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 (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-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) was pointed to the Swift GRB190631. (trigger No 912239, 19h 35m 37.92s , -32d 45m 03.60s, R=0.05) errorbox 50 sec after trigger time at 2019-06-30 23:53:49 UT, with upper limit up to 17.8 mag. Observations started at twilight. The observations began at zenit distance = 78 deg. The sun altitude is -16.8 deg. MASTER-OAFA robotic telescope located in Argentina (OAFA observatory of San Juan National University) was pointed to the Swift GRB190631. errorbox 56 sec after trigger time at 2019-06-30 23:53:55 UT, with upper limit up to 17.6 mag. The observations began at zenit distance = 71 deg. The sun altitude is -27.2 deg. MASTER-IAC robotic telescope located in Spain (IAC Teide Observatory) was pointed to the Swift GRB190631. errorbox 83 sec after trigger time at 2019-06-30 23:54:22 UT, with upper limit up to 18.8 mag. The observations began at zenit distance = 68 deg. The sun altitude is -36.0 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=1061706 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_____________________|_____|_______|______|________ 55 | MASTER-Tavrida | C | 10 | 16.5 | 61 | MASTER-OAFA | C | 10 | 16.5 | 94 | MASTER-IAC | P| | 20 | 17.5 | 94 | MASTER-IAC | P- | 20 | 17.2 | 94 | MASTER-Tavrida | C | 20 | 17.2 | 117 | MASTER-OAFA | C | 20 | 17.0 | 143 | MASTER-Tavrida | C | 30 | 17.4 | 150 | MASTER-IAC | P| | 30 | 17.8 | 150 | MASTER-IAC | P- | 30 | 17.5 | 184 | MASTER-OAFA | C | 30 | 17.2 | 202 | MASTER-Tavrida | C | 40 | 17.6 | 204 | MASTER-IAC | P- | 40 | 17.6 | 204 | MASTER-IAC | P| | 40 | 18.1 | 267 | MASTER-OAFA | C | 50 | 17.5 | 269 | MASTER-IAC | P| | 50 | 18.3 | 269 | MASTER-IAC | P- | 50 | 17.9 | 271 | MASTER-Tavrida | C | 50 | 17.8 | 343 | MASTER-IAC | P| | 60 | 18.5 | 343 | MASTER-IAC | P- | 60 | 18.1 | 368 | MASTER-OAFA | C | 70 | 17.6 | 434 | MASTER-IAC | P- | 80 | 18.3 | 435 | MASTER-IAC | P| | 80 | 18.7 | 544 | MASTER-IAC | P- | 100 | 18.5 | 544 | MASTER-IAC | P| | 100 | 18.8 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.