TITLE: GCN CIRCULAR NUMBER: 26113 SUBJECT: Swift GRB191031.89: Global MASTER-Net observations report DATE: 19/10/31 22:09:22 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 GRB191031.89 (trigger No 932608,18h 53m 06.000s , +47d 38m 20.40s, R=0.05) errorbox 14 sec after notice time and 551 sec after trigger time at 2019-10-31 21:32:42 UT, with upper limit up to 17.4 mag. The observations began at zenith distance = 71 deg. The sun altitude is -60.1 deg. MASTER-IAC robotic telescope located in Spain (IAC Teide Observatory) was pointed to the Swift GRB191031.89 errorbox 48 sec after notice time and 585 sec after trigger time at 2019-10-31 21:33:17 UT, with upper limit up to 19.0 mag. The observations began at zenith distance = 53 deg. The sun altitude is -43.2 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=1183931 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_____________________|_____|_______|______|________ 607 | MASTER-Tavrida | C | 110 | 16.9 | 762 | MASTER-Tavrida | C | 420 | 17.4 | Coadd 646 | MASTER-IAC | P| | 120 | 18.4 | 811 | MASTER-IAC | P| | 450 | 19.0 | Coadd 646 | MASTER-IAC | P- | 120 | 18.3 | 745 | MASTER-Tavrida | C | 140 | 16.7 | 808 | MASTER-IAC | P| | 150 | 18.5 | 808 | MASTER-IAC | P- | 150 | 18.4 | 914 | MASTER-Tavrida | C | 170 | 16.5 | 1013 | MASTER-IAC | P| | 180 | 18.4 | 1013 | MASTER-IAC | P- | 180 | 18.3 | 1103 | MASTER-Tavrida | C | 180 | 16.0 | 1103 | MASTER-Tavrida | C | 180 | 15.5 | 1255 | MASTER-IAC | P| | 180 | 18.5 | 1255 | MASTER-IAC | P- | 180 | 18.3 | 1304 | MASTER-Tavrida | C | 180 | 16.1 | 1304 | MASTER-Tavrida | C | 180 | 15.7 | 1498 | MASTER-IAC | P- | 180 | 18.3 | 1498 | MASTER-IAC | P| | 180 | 18.3 | 1505 | MASTER-Tavrida | C | 180 | 15.9 | 1505 | MASTER-Tavrida | C | 180 | 14.8 | 1706 | MASTER-Tavrida | C | 180 | 15.0 | 1706 | MASTER-Tavrida | C | 180 | 14.1 | 1738 | MASTER-IAC | P| | 180 | 14.8 | 1738 | MASTER-IAC | P- | 180 | 14.7 | 1907 | MASTER-Tavrida | C | 180 | 14.3 | 1907 | MASTER-Tavrida | C | 180 | 15.8 | 1989 | MASTER-IAC | P| | 180 | 18.4 | 1989 | MASTER-IAC | P- | 180 | 18.2 | 2108 | MASTER-Tavrida | C | 180 | 16.6 | 2108 | MASTER-Tavrida | C | 180 | 16.6 | 2230 | MASTER-IAC | P- | 180 | 18.1 | 2230 | MASTER-IAC | P| | 180 | 18.2 | 2309 | MASTER-Tavrida | C | 180 | 17.2 | 2309 | MASTER-Tavrida | C | 180 | 17.3 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.