TITLE: GCN CIRCULAR NUMBER: 24776 SUBJECT: Fermi trigger No 581841498 Global MASTER-Net observations report DATE: 19/06/10 17:32:00 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-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 Fermi GRB190610.28 (trigger No 581841498, 10h 22m 04.08s , -47d 1m 01.20s, R=24.63) errorbox 36430 sec after trigger time at 2019-06-10 16:45:23 UT, with upper limit up to 19.3 mag. Observations started at twilight. The observations began at zenit distance = 19 deg. The sun altitude is -13.4 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/observ.php?id=1044320 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 36520 | 2019-06-10 16:45:23 | MASTER-SAAO | ( 11h 59m 16.63s , -52d 32m 36.30s) | I | 180 | 16.7 | 36732 | 2019-06-10 16:48:54 | MASTER-SAAO | ( 11h 59m 18.50s , -52d 32m 46.65s) | I | 180 | 17.3 | 36912 | 2019-06-10 16:48:54 | MASTER-SAAO | ( 11h 59m 18.50s , -52d 32m 46.71s) | I | 540 | 18.0 | Coadd 36943 | 2019-06-10 16:52:26 | MASTER-SAAO | ( 11h 59m 18.86s , -52d 32m 33.85s) | I | 180 | 17.5 | 37160 | 2019-06-10 16:56:02 | MASTER-SAAO | ( 11h 59m 18.17s , -52d 32m 38.31s) | I | 180 | 17.6 | 37553 | 2019-06-10 16:59:35 | MASTER-SAAO | ( 11h 59m 18.60s , -52d 33m 04.63s) | V | 540 | 19.3 | Coadd The observation and reduction will continue. The message may be cited.