TITLE: GCN CIRCULAR NUMBER: 23616 SUBJECT: GRB 190106A: MASTER Amur OT detection DATE: 19/01/06 14:20:15 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, A.Kuznetsov, E. Gorbovskoy, V.Kornilov, D.Kuvshinov, N.Tyurina, P.Balanutsa,D. Vlasenko Lomonosov Moscow State University, Sternberg Astronomical Institute, Moscow State University V. Yurkov, A. Gabovich, Yu. Sergienko, D. Kobcev Blagoveschensk Educational State University, Blagoveschensk 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 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-Amur robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Blagoveshchensk State Pedagogical University) was pointed to the GRB190106.57 (Swift BAT alert, GCN 23615) 20 sec after notice time and 36 sec after trigger time at 2019-01-06 13:35:20 UT. On our first (10s exposure) set we found optical transient within SWIFT BAT error-box (ra=29.8792 dec=23.8567 r=0.05). The 5-sigma upper limit has been about 16.5mag RA, DEC = 01h 59m 31.20s +23d 50m 44.04s mag = 16.0 The automatical photometry are: start time coord2000 Band mag emag exp 13:35:20.0 1h 59m 31.17s +23d 50m 44.5s P 16.2 0.20 10 13:35:46.6 1h 59m 31.19s +23d 50m 44.8s P 15.2 0.14 10 13:36:12.6 1h 59m 31.23s +23d 50m 44.1s P 15.8 0.15 20 13:36:47.8 1h 59m 31.19s +23d 50m 44.6s P 16.2 0.17 20 13:37:24.9 1h 59m 31.23s +23d 50m 44.5s P 15.8 0.11 30 13:38:08.7 1h 59m 31.18s +23d 50m 44.2s P 15.4 0.08 40 13:39:03.1 1h 59m 31.17s +23d 50m 44.2s P 15.7 0.07 50 13:40:07.0 1h 59m 31.18s +23d 50m 44.1s P 15.5 0.09 60 13:41:35.5 1h 59m 31.20s +23d 50m 44.0s P 15.6 0.10 60 13:43:03.7 1h 59m 31.18s +23d 50m 44.3s P 15.9 0.11 60 13:44:28.9 1h 59m 31.18s +23d 50m 43.8s P 16.1 0.12 60 ............................... to be continuated... This optical counterpart is coincident with Swift optical object (Sonbas et al., GCN 23615). The galactic latitude b = -36 deg., longitude l = 143 deg. The observations made on zenit distance = 45 deg.The moon ( 0 % bright part) below the horizon (The altitude of the Moon is -50 deg. ). The sun altitude is -53.7 deg. The object can be observed till 2019-01-07 18:34:53 This message may be cited, but this is the first automatic photometry. Non monotonic light curve was detected.