TITLE: GCN CIRCULAR NUMBER: 20903 SUBJECT: IceCube-170312A: MASTER follow-up observations DATE: 17/03/18 10:12:27 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs N.V.Tyurina, V.M. Lipunov, E.S. Gorbovskoy, A.S.Kuznetsov, P.Balanutsa, V.V.Vladimirov, V.V.Chazov, D.Kuvshinov Lomonosov Moscow State University, Sternberg Astronomical Institute D.Buckley, S. Potter, A.Kniazev, M.Kotze, South African Astronomical Observatory R. Rebolo, M. Serra-Ricart, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias K.Ivanov, O.Gress, N.M.Budnev, S.Yazev, O.Chuvalaev, V.A.Poleshchuk, Irkutsk State University A. Tlatov, V.Senik, D. Dormidontov, Kislovodsk Solar Station of the Pulkovo Observatory H. Levato, C. Saffe, Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE) R. Podesta, C. Lopez, F.Podest Observatorio Astronomico Felix Aguilar (OAFA) A.Gabovich, V.Yurkov, Yu.Sergienko Blagoveschensk Educational State University, Blagoveschensk MASTER Global Robotic Net was starting inspection of IceCube HESE neutrino alert IceCube-170312A (Blaufuss et al. GCN #20857: RA(2000)= 305.15 -26.61, Triggertime= 2017-03-12 13:49:39.83 UT) on 2017-03-13 02:06:34UT at MASTER-SAAO (Object: Altitude: 20.35, Sun: Altitude: -30.72,Dist. to Moon: 123.282677, Moon disk: 0.997328) and on 2017-03-14 08:38:51UT at MASTER-OAFA (Object: Altitude: 27.61, Sun: Altitude: -25.02,Dist. to Moon: 107.465652, Moon disk: 0.968195). MASTER-II is 2x4sq.degrees (Lipunov et al., 2010, Advances in Astronomy, 2010, 30L) At alert time the state at MASTER observatories are: MASTER-Amur Object: Altitude: -61.72 Sun: Altitude: -37.55 MASTER-Tunka Object: Altitude: -64.60 Sun: Altitude: -25.23 MASTER-Kislovodsk Object: Altitude: -35.78 Sun: Altitude: 13.57 MASTER-SAAO Object: Altitude: 11.19 Sun: Altitude: 37.97, inspect on13 Mar, mlim=19.2, 20 images MASTEC-IAC(Tenerife) Object: Altitude: 13.06 Sun: Altitude: 57.41 MASTER-OAFA(Argentina) Object: Altitude: 84.05 Sun: Altitude: 39.69, inspect on 13,19 Mar, mlim=18.5-19.1, 16 images MASTER auto-detection software doesn't detect optical transient, that can be connected with IC alert. We analized SWIFT Xray sources (Keivani et al., GCN#20890) 1) 20 21 21.41 -26 01 32.3 There is no optical sources up to unfiltered mlim=19.2 during MASTER-SAAO inspection of this IC170312 alert on 2017-03-13 02:37:14UT, and mlim=18.5 (2017-03-14 08:38:51UT), mlim=18.7(2017-03-18 07:38:23UT) in MASTER-OAFA . There is a faint MASTER optical detection with m<< (unfiltered mlim=19.9) in MASTER-IAC database on 2016-07-28 00:13:46UT. The nearest optical source in VIZIER database is in 5.5", also GALEX source(offset is 6.7"). 2)20 21 54.52 -26 04 12.0 There is a variable optical source in MASTER database (17.5-18.7 MASTER-IAC, MASTER-SAAO) with m_OT=18.3 on 2017-03-13 02:59:57.059UT (MASTER-SAAO) There is a GALEX source in 2.6", also optical (USNO,etc) and possible AGN (Secrest+, 2015). http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=&-out.add=_r&-out.add=_RAJ%2C_DEJ&-sort=_r&-to=&-out.max=20&-meta.ucd=2&-meta.foot=1&-c=305.47716666667+-26.07&-c.rs=5 3) 20 18 26.4s -26 50 24.6 Variable optical source in MASTER database : m_OT=18.7 on 2017-03-13 02:59:57.059UT (MASTER-SAAO) 17.8(2016-10-21 00:34:28.062UT) - 18.8 (2017-03-18 07:34:39.474) MASTER-OAFA 4) 20 16 34.69 -26 38 56.6 There is no optical sources brighter then unfiltered mlim=19.2 during MASTER-SAAO inspection on 2017-03-13 02:24:33UT, and in archive images in MASTER-IAC on 2016-07-11 01:42:30UT with mlim=20.2 There is no sources in VIZIER 5) 20 19 25.94 -26 06 09.9 There is an optical source in MASTER-SAAO with m_OT~19.3 (mlim=19.5) There is USNO-B1 star with R1=19.20, B2=20.44 in 1.6", also candidate to AGN (Secrest+, 2015). http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=&-out.add=_r&-out.add=_RAJ%2C_DEJ&-sort=_r&-to=&-out.max=20&-meta.ucd=2&-meta.foot=1&-c=304.85808333333+-26.10275&-c.rs=5 The message may be cited.