TITLE: GCN CIRCULAR NUMBER: 24294 SUBJECT: Fermi GRB190427.19 Global MASTER-Net observations report DATE: 19/04/27 18:17:03 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-Tunka robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Applied Physics Institute, Irkutsk State University) started inspect of the Fermi GRB190427.19 ( 18h 10m 04.08s , +46d 49m 58.80s, R=3.5) errorbox 45378 sec after trigger time at 2019-04-27 17:10:33 UT, with upper limit up to 19.8 mag. The observations began at zenit distance = 36 deg. The sun altitude is -25.2 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=1004400 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 45468 | 2019-04-27 17:10:33 | MASTER-Tunka | ( 17h 57m 43.43s , +46d 10m 42.11s) | C | 180 | 19.4 | 45468 | 2019-04-27 17:10:33 | MASTER-Tunka | ( 18h 7m 26.47s , +45d 59m 55.38s) | C | 180 | 19.8 | 46124 | 2019-04-27 17:21:29 | MASTER-Tunka | ( 17h 57m 41.81s , +46d 10m 55.77s) | C | 180 | 19.2 | 46124 | 2019-04-27 17:21:29 | MASTER-Tunka | ( 18h 7m 25.60s , +46d 0m 08.49s) | C | 180 | 19.8 | 46415 | 2019-04-27 17:26:19 | MASTER-Tunka | ( 17h 57m 42.87s , +46d 11m 01.93s) | C | 180 | 19.4 | 46415 | 2019-04-27 17:26:19 | MASTER-Tunka | ( 18h 7m 26.54s , +46d 0m 14.87s) | C | 180 | 19.8 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.