TITLE: GCN CIRCULAR NUMBER: 23949 SUBJECT: GRB190311A: MASTER Global Robotic Net OT optical observation DATE: 19/03/11 16:18:57 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs E. Gorbovskoy, V. Lipunov, E. Gorbovskoy, N.Tyurina, V.Kornilov, D.Vlasenko, V.Vladimirov, D.Zimnukhov, A.Kuznetsov, P.Balanutsa, A. Chasovnikov, D.Kuvshinov (Lomonosov Moscow State University, SAI, Physics Department), O. Gress, N.M. Budnev, O.Ershova, Yu.Ishmuhametova (Applied Physics Institute, Irkutsk State University), V. Yurkov, A. Gabovich, Yu. Sergienko, D. Kobcev (Blagoveschensk Educational State University), R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), A. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), R. Podesta, C. Lopez, C.Francile, F. Podesta (Observatorio Astronomico Felix Aguilar OAFA), H.Levato (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE) MASTER-Tunka robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Applied Physics Institute, Irkutsk State University) was pointed to the GRB190311.6 (Troja et al., 23946) 55 sec after notice time and 66 sec after trigger time at 2019-03-11 14:24:45 UT. On our third (30 s exposure) set we found optical transient within SWIFT error-box at Swift UVOT position (Troja et al., 23946). m ~ 17.5 RA, DEC = 14:08:15.72, +53:30:02.9 err = 1 arcsec We obtain a following images with OT: Tmid-T0 | Site |Filt.| Expt. | Limit | Comment _________|_____________________|_____|_______|_______|________ 109 | MASTER-Tunka | P- | 10 | 16.82 | 109 | MASTER-Tunka | P- | 80 | 18.47 | Coadd 109 | MASTER-Tunka | P| | 10 | 16.69 | 109 | MASTER-Tunka | P| | 80 | 18.33 | Coadd 231 | MASTER-Tunka | P| | 30 | 17.60 | 231 | MASTER-Tunka | P- | 30 | 17.74 | 338 | MASTER-Tunka | P| | 40 | 17.70 | 338 | MASTER-Tunka | P- | 40 | 17.87 | 462 | MASTER-Amur | P/ | 60 | 13.12 | 465 | MASTER-Tunka | P| | 60 | 18.12 | 465 | MASTER-Tunka | P| | 250 | 19.14 | Coadd 465 | MASTER-Tunka | P- | 60 | 18.21 | 465 | MASTER-Tunka | P- | 250 | 19.24 | Coadd 593 | MASTER-Amur | P/ | 60 | 12.20 | 614 | MASTER-Tunka | P| | 80 | 18.50 | 614 | MASTER-Tunka | P- | 80 | 18.43 | 808 | MASTER-Tunka | P| | 110 | 18.65 | 808 | MASTER-Tunka | P- | 110 | 18.65 | 1032 | MASTER-Tunka | P| | 140 | 18.56 | 1032 | MASTER-Tunka | P| | 490 | 19.35 | Coadd 1032 | MASTER-Tunka | P- | 140 | 18.55 | 1032 | MASTER-Tunka | P- | 490 | 19.30 | Coadd 1305 | MASTER-Tunka | P| | 170 | 18.64 | 1305 | MASTER-Tunka | P- | 170 | 18.63 | 1622 | MASTER-Tunka | P| | 180 | 19.02 | 1623 | MASTER-Tunka | P- | 180 | 18.89 | 1949 | MASTER-Tunka | P| | 180 | 17.67 | 1949 | MASTER-Tunka | P| | 540 | 19.26 | Coadd 1949 | MASTER-Tunka | P- | 180 | 17.63 | 1949 | MASTER-Tunka | P- | 540 | 19.22 | Coadd 2284 | MASTER-Tunka | P| | 180 | 18.90 | 2284 | MASTER-Tunka | P- | 180 | 18.98 | 2616 | MASTER-Tunka | P| | 180 | 19.01 | 2949 | MASTER-Tunka | P| | 180 | 19.10 | 2949 | MASTER-Tunka | P| | 540 | 19.83 | Coadd 2949 | MASTER-Tunka | P- | 540 | 19.72 | Coadd 3959 | MASTER-Tunka | P- | 540 | 19.60 | Coadd 3959 | MASTER-Tunka | P| | 540 | 19.87 | Coadd 5650 | MASTER-Tunka | P| | 180 | 19.20 | 5650 | MASTER-Tunka | P- | 180 | 18.89 | 5979 | MASTER-Tunka | P- | 180 | 18.74 | 5979 | MASTER-Tunka | P| | 180 | 19.02 | 6312 | MASTER-Tunka | P| | 180 | 18.66 | 6312 | MASTER-Tunka | P- | 180 | 18.79 | The 5-sigma upper limit has been about 16.32mag The message may be cited. ==================================================================== The galactic latitude b = 60 deg., longitude l = 99 deg. The observations made on zenit distance = 48 deg.The moon (22 % bright part) is 14 deg. above the horizon. The distance between moon and object is 113 The sun altitude is -30.2 deg. The object can be observed till sunrise at 2019-03-12 23:26:58. This message can be cited.