TITLE: GCN CIRCULAR NUMBER: 24663 SUBJECT: Fermi GRB190525.03 Global MASTER-Net observations report DATE: 19/05/25 01:31:18 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Vladimirov, D. Vlasenko, 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 GRB190525.03 (trigger No 580437952, 22h 21m 21.60s , + 7d 25m 12.00s, R=3.44) errorbox 70 sec after trigger time at 2019-05-25 00:46:57 UT, with upper limit up to 18.5 mag. The observations began at zenit distance = 70 deg. The sun altitude is -58.7 deg. MASTER-Kislovodsk robotic telescope located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the Fermi GRB190525.03 errorbox 88 sec after trigger time at 2019-05-25 00:47:15 UT, with upper limit up to 12.5 mag. Observations started at twilight. The observations began at zenit distance = 49 deg. The sun altitude is -8.7 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=1027971 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 76 | 2019-05-25 00:46:57 | MASTER-SAAO | ( 22h 25m 08.03s , + 7d 22m 00.38s) | C | 10 | 15.9 | 101 | 2019-05-25 00:46:57 | MASTER-SAAO | ( 22h 25m 08.03s , + 7d 22m 00.36s) | C | 60 | 16.8 | Coadd 98 | 2019-05-25 00:47:15 | MASTER-Kislovodsk | ( 22h 23m 56.61s , + 7d 9m 16.89s) | C | 20 | 12.2 | 120 | 2019-05-25 00:47:37 | MASTER-SAAO | ( 22h 25m 14.17s , + 7d 22m 10.90s) | C | 20 | 16.3 | 148 | 2019-05-25 00:47:59 | MASTER-Kislovodsk | ( 22h 15m 30.74s , + 7d 36m 52.69s) | C | 30 | 12.5 | 148 | 2019-05-25 00:48:00 | MASTER-Kislovodsk | ( 22h 23m 56.61s , + 7d 9m 17.96s) | C | 30 | 12.1 | 174 | 2019-05-25 00:48:26 | MASTER-SAAO | ( 22h 25m 14.19s , + 7d 22m 13.75s) | C | 30 | 16.5 | 240 | 2019-05-25 00:49:27 | MASTER-SAAO | ( 22h 25m 14.22s , + 7d 22m 16.38s) | C | 40 | 16.8 | 310 | 2019-05-25 00:49:27 | MASTER-SAAO | ( 22h 25m 14.22s , + 7d 22m 16.32s) | C | 180 | 17.4 | Coadd 319 | 2019-05-25 00:50:36 | MASTER-SAAO | ( 22h 25m 14.26s , + 7d 22m 18.57s) | C | 60 | 16.9 | 654 | 2019-05-25 00:55:40 | MASTER-SAAO | ( 22h 35m 55.88s , + 5d 23m 55.73s) | C | 120 | 18.0 | 819 | 2019-05-25 00:55:40 | MASTER-SAAO | ( 22h 35m 55.89s , + 5d 23m 55.71s) | C | 450 | 18.5 | Coadd 820 | 2019-05-25 00:58:11 | MASTER-SAAO | ( 22h 36m 00.68s , + 5d 24m 04.87s) | C | 150 | 18.3 | 1015 | 2019-05-25 01:01:12 | MASTER-SAAO | ( 22h 36m 00.70s , + 5d 24m 07.35s) | C | 180 | 18.3 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.