TITLE: GCN CIRCULAR NUMBER: 23587 SUBJECT: FRB 181228: Global MASTER Net optical inspection DATE: 18/12/29 10:34:28 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs E. Gorbovskoy, V. Lipunov, N.Tiurina, V.Kornilov, P.Balanutsa, A.Kuznetsov, D.Vlasenko, F.Balakin (Lomonosov Moscow State University, SAI), R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar), H. Levato (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio of San Juan National University, Argentina) 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, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), O. Gress, N.M. Budnev, S. Yazev, O. Chuvalaev (Irkutsk State University, API) V. Yurkov, A. Gabovich, D.Kobtsev, Yu. Sergienko (Blagoveschensk Educational State University) MASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) was pointed to the FRB 181228A ( Ferah et al, #ATel 12335 ) 17723 sec after trigger time at 2018-12-28 18:44:13 UT, with upper limit up to 22.0 mag. Observations started at twilight, immediately after sunset. The observations began at zenit distance = 43 deg. The sun altitude is -11.0 deg. MASTER-OAFA robotic telescope located in Argentina (OAFA observatory of San Juan National University) was pointed to the FRB Alert181228.58 57672 sec after trigger time at 2018-12-29 05:50:03 UT, with upper limit up to 19.0 mag. The observations began at zenit distance = 24 deg. The sun altitude is -33.0 deg. The galactic latitude b = -60 deg., longitude l = 98 deg. MASTER-OAFA auto-detection system ( Lipunov et al., "MASTER Global Robotic Net", Advances in Astronomy, 2010, 30L ) discovered OT source at (RA, Dec) = 06h 09m 25.17s -47d 32m 48.6s on 2018-12-29.34613 UT. The OT unfiltered magnitude is 17.9 m. The OT is seen in 2 images. There is no minor planet at this place. OT is also visible on 3 MASTER-SAAO images today night. We have reference image without OT on 2017-11-11.33303 UT with magnitude limit in 'BLANK' filter 19.9m. The Possible Super Nova discovered in PGC 499631 Galaxy (OT off set from galaxy are 0.4W 2.5N), approximately 1.5 degree far away from FRG errorline. Its not coonected with FRB. Spectral observations are required. The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/060925.17-473248.6.png Real time updated cover map available here: http://master.sai.msu.ru/static//FRB/db/FRB181228A/img/FRB.png The message may be cited.