TITLE: GCN CIRCULAR NUMBER: 28268 SUBJECT: Baksan Neutrino Observatory Alert 200819.88: Global MASTER-Net observations report DATE: 20/08/19 22:00:10 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, N.Tyurina, V.Kornilov, P.Balanutsa, I.Gorbunov, D.Vlasenko, V.Vladimirov, A.Kuznetsov, A. Chasovnikov, V.Topolev, D.Kuvshinov, F.Balakin, V.A. Senik (Lomonosov Moscow State University, SAI, Physics Department), V.B. Petkov, M.M. Boliev, A.N. Kurenya, (Baksan Neutrino Observatory, Institute for Nuclear Research of RAS, Moscow, Russia), R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), N.M. Budnev, O. Gress, O.Ershova (Applied Physics Institute, Irkutsk State University), V. Yurkov, A. Gabovich, Yu. Sergienko, D. Kobcev (Blagoveschensk Educational State University), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), R. Podesta, C. Lopez, C.Francile, F. Podesta (Observatorio Astronomico Felix Aguilar OAFA, San Juan National University), H.Levato (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE SJNU) 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 Baksan Neutrino Observatory Alert 200819.88 (trigger No 1648587875,17h 16m 00.00s , -32d 54m 00.0s, R=3) errorbox 72 sec after notice time and 951 sec after trigger time at 2020-08-19 21:20:26 UT, with upper limit up to 19.1 mag. The observations began at zenith distance = 43 deg. The sun altitude is -62.9 deg. The galactic latitude b = 3 deg., longitude l = 354 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1422805 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 1042 | 2020-08-19 21:20:26 | MASTER-SAAO | (17h 10m 02.16s , -32d 53m 15.3s) | C | 180 | 17.5 | 1042 | 2020-08-19 21:20:26 | MASTER-SAAO | (17h 18m 23.28s , -32d 52m 36.9s) | C | 180 | 18.9 | 1241 | 2020-08-19 21:23:46 | MASTER-SAAO | (17h 09m 56.22s , -32d 54m 07.4s) | C | 180 | 17.5 | 1241 | 2020-08-19 21:23:46 | MASTER-SAAO | (17h 18m 17.42s , -32d 53m 29.7s) | C | 180 | 19.1 | 1441 | 2020-08-19 21:27:05 | MASTER-SAAO | (17h 09m 55.50s , -32d 53m 07.0s) | C | 180 | 17.6 | 1441 | 2020-08-19 21:27:05 | MASTER-SAAO | (17h 18m 16.59s , -32d 52m 30.2s) | C | 180 | 19.1 | 1640 | 2020-08-19 21:30:25 | MASTER-SAAO | (17h 18m 24.21s , -32d 53m 30.9s) | C | 180 | 19.1 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.