TITLE: GCN CIRCULAR NUMBER: 15879 SUBJECT: GRB 140219A: MASTER optical brightening inside XRT-5 error box detection DATE: 14/02/23 15:59:55 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, M. Pruzhinskaya, E. Gorbovskoy, D.Denisenko, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.V.Chazov, D.Kuvshinov Lomonosov Moscow State University, Sternberg Astronomical Institute K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov Blagoveschensk Educational State University, Blagoveschensk A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory V.Krushinski, I.Zalozhnih, A. Popov Ural Federal University, Kourovka Hugo Levato and Carlos Saffe Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE) Claudio Mallamaci, Carlos Lopez and Federico Podest Observatorio Astronomico Felix Aguilar (OAFA) We refined our reduction of images started 18h 22m after trigger time (Gorbovskoy et al., GCN 15871). We found the 3-sigma OT on several (at least 4) best unfiltered images with limit ~ 20 mag inside XRT error box (Mangano and Evans, GCN 15875) at automatic position: 2014-02-20 14:08:50.873 10h 24m 06.46s , +06d 29m 40s.8 with 2 arcsec error (2 arcsec = 1 pix). The unfiltered magnitude is about 19. Fortunately we have archive images of this area at the same telescope with slightly better limit(MASTER II, Tunka,2011-02-06 16:34:55 180) without any optical source. The OT is brighter at least 1 magnitude at 18.5 hours after trigger. The OT position does not coincide with SDSS J102406.58+062945.7 galaxy (Singer, iPTF GCN 15878, source XRT 5), closer to SDSS star J102406.41+062937.6 . The detection and reference images are available at http://master.sai.msu.ru/static/GRB/GRB140219A_OT.png We do not see any OT at alert Very Wide Field images at this place (Gorbovskoy et al., GCN 15871). The message may be cited.