TITLE: GCN CIRCULAR NUMBER: 24416 SUBJECT: IceCube-190504A: MASTER optical monitoring analysis DATE: 19/05/07 10:57:24 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, O. Gress, E. Gorbovskoy, N.Tyurina, V.Kornilov, P.Balanutsa, D.Vlasenko, F.Balakin, V.Vladimirov, D.Zimnukhov, A.Kuznetsov, A. Chasovnikov, V.Topolev(Lomonosov Moscow State University, SAI, Physics Department), R. Podesta, C. Lopez, C.Francile, F. Podesta (Observatorio Astronomico Felix Aguilar OAFA, San Juan National University), H.Levato (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE, SJNU) R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), N.M. Budnev, O.Ershova (Applied Physics Institute, Irkutsk State University), V. Yurkov, A. Gabovich, Yu. Sergienko, D. Kobcev (Blagoveschensk Educational State University), A. Tlatov, V.Senik, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), MASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South African Astronomical Observatory was pointed to the IceCube-190504A (Kopper et al. GCN 24392) alert 39 sec after notice time (133 sec after trigger time) at 2019-05-04 18:27:31 UT (Lipunov et al. GCN 24395). MASTER-OAFA robotic telescope started IceCube-190504A inspection at 2019-05-04 23:10:52.949 UT. MASTER auto-detection system didn't find new or variable sources, that can be connected with this alert. But. MASTER observed this error-box during the following GRB/LVC alerts observations: event_name | grbtime | GRBcenter_coord2000 |Er.B.deg|Exper.| MASTERobs_starttime | mlim. --------------+---------------------+-------------------------------+-------+---------+-------------------------+------- GRB190504.77 | 2019-05-04 18:25:18 | ( 4h 23m 09s , -37d 26m 35s) | 1.2 | ICECUBE | 2019-05-04 18:27:31 | 18.6 GRB190313.15 | 2019-03-13 03:36:00 | ( 4h 27m 52s , -37d 12m 00s) | 14.3 | FERMI | 2019-03-13 20:40:04 | 18.8 GW190425 | 2019-04-29 00:21:41 | LVC S190425z | | LVC | 2019-04-29 00:06:38 | 18.3 GRB180826.06 | 2018-08-26 01:19:15 | ( 4h 09m 50s , -22d 26m 59s | 6.9 | FERMI | 2018-08-29 02:38:42 | 19.6 GRB180508.64 | 2018-05-08 15:23:50 | ( 3h 50m 48s , -39d 12m 00s) | 9.1 | FERMI | 2018-05-09 16:55:07 | 19.0 GRB180423.34 | 2018-04-23 08:16:05 | ( 7h 13m 24s , -30d 30m 00s) | 37.9 | FERMI | 2018-04-24 18:17:15 | 18.5 GRB180311.07 | 2018-03-11 01:45:53 | ( 4h 28m 24s , -43d 18m 00s) | 11.1 | FERMI | 2018-03-11 20:37:31 | 19.4 GRB180309.14 | 2018-03-09 03:28:35 | ( 3h 55m 52s , -39d 25m 00s) | 12.7 | FERMI | 2018-03-10 02:37:03 | 18.6 GRB180114.45 | 2018-01-14 10:42:23 | ( 3h 40m 40s , -44d 9m 00s) | 10.4 | FERMI | 2018-01-14 21:11:40 | 18.1 GRB171121.83 | 2017-11-21 20:01:59 | ( 5h 7m 40s , -36d 58m 00s) | 8.7 | FERMI | 2017-11-22 01:37:28 | 19.3 GRB171004.78 | 2017-10-04 18:46:40 | ( 2h 56m 40s , -37d 10m 59s) | 26.6 | FERMI | 2017-10-06 21:05:18 | 18.7 GRB171004.67 | 2017-10-04 16:07:16 | ( 5h 22m 52s , -26d 15m 00s) | 17.0 | FERMI | 2017-10-06 21:05:18 | 18.7 GRB170422.37 | 2017-04-22 08:58:23 | ( 4h 17m 52s , -45d 52m 60s) | 18.4 | FERMI | 2017-04-24 23:04:59 | 18.3 GRB170307.22 | 2017-03-07 05:15:05 | ( 4h 18m 48s , -30d 58m 60s) | 6.4 | FERMI | 2017-03-07 19:49:33 | 18.9 GRB160430.35 | 2016-04-30 08:22:08 | ( 2h 58m 56s , -16d 34m 00s) | 36.6 | FERMI | 2016-04-30 16:54:00 | 18.9 GRB160319.34 | 2016-03-19 08:08:10 | ( 2h 57m 52s , -14d 24m 00s) | 35.5 | FERMI | 2016-03-19 19:29:48 | 18.5 GRB150824.55 | 2015-08-24 13:14:25 | ( 4h 2m 56s , -46d 43m 60s) | 13.4 | FERMI | 2015-08-26 02:14:38 | 20.3 GRB150806.63 | 2015-08-06 15:07:37 | ( 3h 55m 12s , -54d 54m 00s) | 34.8 | FERMI | 2015-08-09 03:34:30 | 19.7 GRB150801.09 | 2015-08-01 02:16:43 | ( 4h 19m 08s , -36d 6m 00s) | 10.9 | FERMI | 2015-08-01 02:17:04 | 15.3 GRB141222.41 | 2014-12-22 09:53:57 | ( 6h 26m 56s , -54d 27m 00s) | 34.7 | FERMI | 2014-12-24 22:12:28 | 19.8 and during own survey Dec2014-May2019. We checked Swift sources (Keivani et al. GCN 24405 )in MASTER database. The 7th source is in maximum in optic now 1) 66.17568d, -37.93938d m_OT=19.6 at 2014-12-24 22:12:28.681, m_OT=19.6 at 2018-11-15 00:47:43.986, m_OT