TITLE: GCN CIRCULAR NUMBER: 25440 SUBJECT: LIGO/Virgo S190822c Global MASTER-Net observations report DATE: 19/08/22 02:17:18 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-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) started inspect of the LIGO/Virgo S190822c errorbox 372 sec after notice time and 859 sec after trigger time at 2019-08-22 01:44:18 UT, with upper limit up to 18.6 mag. The observations began at zenit distance = 7 deg. The sun altitude is -45.7 deg. MASTER-SAAO robotic telescope located in South Africa (South African Astronomical Observatory) started inspect of the LIGO/Virgo S190822c errorbox 522 sec after notice time and 1009 sec after trigger time at 2019-08-22 01:46:48 UT, with upper limit up to 18.2 mag. The observations began at zenit distance = 73 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/ligo_1.php?id=10722 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 949 | 2019-08-22 01:44:18 | MASTER-OAFA | ( 19h 29m 03.42s , -26d 1m 48.37s) | C | 180 | 18.6 | 1100 | 2019-08-22 01:46:48 | MASTER-SAAO | ( 19h 28m 42.23s , -24d 2m 45.23s) | C | 180 | 18.2 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.