TITLE: GCN CIRCULAR NUMBER: 23299 SUBJECT: GRB 181003A: MASTER optical observation DATE: 18/10/03 13:57:37 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, D.Kuvshinov, N.Tyurina, P.Balanutsa,A.Kuznetsov, V.V.Chazov, D. Vlasenko Lomonosov Moscow State University, Sternberg Astronomical Institute R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias 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, South African Astronomical Observatory A. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory O. Gres, N.M. Budnev, Yu.Ishmuhametova Applied Physics Institute of Irkutsk State University V. Yurkov, A. Gabovich, Yu. Sergienko Blagoveschensk Educational State University, Blagoveschensk MASTER-IAC robotic telescope (MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Spain (IAC Teide Observatory) was pointed to Swift GRB181003A (Beardmore et al. GCN 23295, Evans et al. GCN 23296) 4 sec after notice time and 59 sec after trigger time at 2018-10-03 05:12:02 UT, with upper limit up to 19.1 mag. The observations started on zenit distance = 65 deg. The sun altitude was -23.8 deg. MASTER-OAFA robotic telescope located in Argentina (OAFA observatory of San Juan National University) was pointed to the GRB181003A 10 sec after notice time and 64 sec after trigger time at 2018-10-03 05:12:08 UT, with upper limit up to 20.3 mag. The observations started on zenit distance = 27 deg. The sun altitude was -53.3 deg. The galactic latitude b = -60 deg., longitude l = 98 deg. We obtained the following upper limits: Tmid-T0 | MASTER observatory |Filt.| Exp.,s| m_lim | Comment _________|_____________________|_____|_______|_______|________ 89 | MASTER-IAC | P- | 10 | 16.29 | 89 | MASTER-IAC | P- | 50 | 17.38 | Coadd 89 | MASTER-IAC | P- | 710 | 19.12 | Coadd 96 | MASTER-OAFA | C | 10 | 16.88 | 96 | MASTER-OAFA | C | 70 | 18.69 | Coadd 96 | MASTER-OAFA | C | 550 | 19.83 | Coadd 131 | MASTER-IAC | P- | 20 | 16.75 | 176 | MASTER-OAFA | C | 20 | 17.54 | 185 | MASTER-IAC | P- | 20 | 16.75 | 242 | MASTER-IAC | P- | 30 | 17.31 | 242 | MASTER-IAC | P- | 120 | 17.94 | Coadd 272 | MASTER-OAFA | C | 40 | 18.17 | 312 | MASTER-IAC | P- | 40 | 17.05 | 393 | MASTER-OAFA | C | 50 | 18.4 | 393 | MASTER-OAFA | C | 210 | 19.3 | Coadd 399 | MASTER-IAC | P- | 50 | 17.53 | 500 | MASTER-IAC | P- | 70 | 17.66 | 500 | MASTER-IAC | P- | 250 | 18.41 | Coadd 531 | MASTER-OAFA | C | 70 | 18.7 | 632 | MASTER-IAC | P- | 80 | 17.66 | 701 | MASTER-OAFA | C | 90 | 18.81 | 774 | MASTER-IAC | P- | 100 | 17.92 | 900 | MASTER-OAFA | C | 120 | 19.05 | 900 | MASTER-OAFA | C | 450 | 19.72 | Coadd 951 | MASTER-IAC | P- | 130 | 17.92 | 1145 | MASTER-OAFA | C | 150 | 19.18 | 1170 | MASTER-IAC | P- | 160 | 17.92 | 1434 | MASTER-OAFA | C | 180 | 19.31 | 1434 | MASTER-OAFA | C | 1800 | 20.16 | Coadd 1436 | MASTER-IAC | P- | 180 | 18.15 | 1436 | MASTER-IAC | P- | 1800 | 19.11 | Coadd 1749 | MASTER-IAC | P- | 180 | 18.16 | 1749 | MASTER-IAC | P- | 540 | 19 | Coadd 1764 | MASTER-OAFA | C | 180 | 19.26 | 1764 | MASTER-OAFA | C | 540 | 19.84 | Coadd 2070 | MASTER-IAC | P- | 180 | 18.16 | 2097 | MASTER-OAFA | C | 180 | 19.27 | 2382 | MASTER-IAC | P- | 180 | 18.16 | 2429 | MASTER-OAFA | C | 180 | 19.3 | 2709 | MASTER-IAC | P- | 180 | 18.14 | 2709 | MASTER-IAC | P- | 540 | 18.97 | Coadd 2760 | MASTER-OAFA | C | 180 | 19.26 | 2760 | MASTER-OAFA | C | 540 | 19.81 | Coadd 3027 | MASTER-IAC | P- | 180 | 18.14 | 3093 | MASTER-OAFA | C | 180 | 19.26 | 3428 | MASTER-OAFA | C | 180 | 19.25 | 3761 | MASTER-OAFA | C | 180 | 19.3 | 3761 | MASTER-OAFA | C | 540 | 19.9 | Coadd 3887 | MASTER-IAC | P- | 180 | 17.93 | 4094 | MASTER-OAFA | C | 180 | 19.27 | 4203 | MASTER-IAC | P- | 180 | 17.89 | 4203 | MASTER-IAC | P- | 540 | 18.43 | Coadd 4428 | MASTER-OAFA | C | 180 | 19.3 | 4515 | MASTER-IAC | P- | 180 | 17.73 | 4758 | MASTER-OAFA | C | 180 | 19.3 | 4758 | MASTER-OAFA | C | 540 | 19.85 | Coadd 4758 | MASTER-OAFA | C | 1800 | 20.26 | Coadd 4835 | MASTER-IAC | P- | 180 | 17.45 | 5093 | MASTER-OAFA | C | 180 | 19.3 | 5151 | MASTER-IAC | P- | 180 | 17.08 | 5151 | MASTER-IAC | P- | 540 | 17.39 | Coadd Filter C is unfiltred band (clear), calibrated by USNO B1 thousands field stars as 0.2B+0.8R. The observation and reduction will continue. The message may be cited.