TITLE: GCN CIRCULAR NUMBER: 24436 SUBJECT: LIGO/Virgo S190510g Global MASTER-Net observations report DATE: 19/05/10 05:16:07 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, D.Kuvshinov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.V.Chazov, D. Vlasenko (Lomonosov Moscow State University, Sternberg Astronomical Institute, Moscow State University) A. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory) K. Ivanov, O. Gres, N.M. Budnev, S. Yazev, O. Chuvalaev, V. Poleshchuk (Irkutsk State University) V. Yurkov, A. Gabovich, Yu. Sergienko (Blagoveschensk Educational State University, Blagoveschensk) R. Podesta, Carlos Lopez and F. Podesta (Observatorio Astronomico Felix Aguilar (OAFA)) Hugo Levato and Carlos Saffe (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)) R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres (The Instituto de Astrofisica de Canarias) D. Buckley, S. Potter, A. Kniazev, M. Kotze (South African Astronomical Observatory) MASTER-IAC robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Spain (IAC Teide Observatory) started inspect of the LIGO/Virgo S190510g errorbox 5366 sec after trigger time at 2019-05-10 04:29:05 UT, with upper limit up to 19.4 mag. The observations began at zenit distance = 82 deg. The sun altitude is -21.9 deg. MASTER-OAFA robotic telescope located in Argentina (OAFA observatory of San Juan National University) started inspect of the LIGO/Virgo S190510g errorbox 5771 sec after trigger time at 2019-05-10 04:35:50 UT, with upper limit up to 19.5 mag. The observations began at zenit distance = 125 deg. The sun altitude is -76.4 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=10342 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 5456 | 2019-05-10 04:29:05 | MASTER-IAC | ( 13h 40m 40.55s , - 3d 55m 12.32s) | C | 180 | 18.0 | 5674 | 2019-05-10 04:32:42 | MASTER-IAC | ( 13h 55m 09.10s , - 1d 55m 34.40s) | C | 180 | 19.1 | 5861 | 2019-05-10 04:35:50 | MASTER-OAFA | ( 13h 31m 14.55s , - 1d 53m 24.34s) | C | 180 | 18.9 | 5904 | 2019-05-10 04:36:33 | MASTER-IAC | ( 13h 55m 08.87s , - 1d 56m 01.81s) | C | 180 | 19.4 | 6086 | 2019-05-10 04:39:34 | MASTER-OAFA | ( 13h 30m 45.90s , + 0d 6m 18.43s) | C | 180 | 19.2 | 6314 | 2019-05-10 04:43:22 | MASTER-OAFA | ( 13h 46m 43.91s , + 0d 6m 21.28s) | C | 180 | 19.5 | 6545 | 2019-05-10 04:47:13 | MASTER-OAFA | ( 13h 31m 12.81s , - 1d 53m 49.56s) | C | 180 | 19.3 | 6770 | 2019-05-10 04:50:58 | MASTER-OAFA | ( 13h 39m 14.80s , - 1d 53m 52.77s) | C | 180 | 19.4 | 7002 | 2019-05-10 04:54:50 | MASTER-OAFA | ( 13h 30m 44.89s , + 0d 6m 29.70s) | C | 180 | 19.3 | 7228 | 2019-05-10 04:58:36 | MASTER-OAFA | ( 13h 38m 43.67s , + 0d 6m 26.15s) | C | 180 | 19.5 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.