TITLE: GCN CIRCULAR NUMBER: 25928 SUBJECT: LIGO/Virgo S190930t: AT2019rpn, AT2019rpj CrAO optical photometry DATE: 19/10/02 19:14:59 GMT FROM: Alexei Pozanenko at IKI, Moscow E. Mazaeva (IKI), V. Rumyantsev (CrAO), A. Pozanenko (IKI), A. Volnova (IKI), S. Belkin (IKI) report on behalf of larger GRB follow-up collaboration: We observed the ZTF19acbpqlh (AT2019rpn) reported by Stein et al. (GCN 25899) and the ATLAS19wyn (AT2019rpj) optical transients with ZTSh 2.6m telescope of CrAO observatory starting on Oct. 01 (UT) 19:30:53. We took several images in B,R filters under good conditions and mean seeing of 1.5 arcsec. Both optical transients are clearly visible in separate images. Preliminary photometry of the optical transients is following Name, UT start T_mid Filter Exp. OT err (MJD) (s) AT2019rpj 2019-10-01 20:16:16 58757.84880 R 11*60 19.37 0.04 AT2019rpj 2019-10-01 20:28:33 58757.85886 B 15*60 19.86 0.04 AT2019rpn 2019-10-01 19:30:53 58757.81861 R 12*60 19.26 0.11 AT2019rpn 2019-10-01 19:47:03 58757.83270 B 11*60 20.17 0.07 The photometry for AT2019rpj is based on the stars: SDSS-DR12_id RA Dec R(Lupton) err B(Lupton) err J223926.51+313057.4 339.860475 +31.515949 17.94 0.02 19.23 0.02 J223929.26+313022.7 339.871951 +31.506316 16.89 0.02 18.52 0.01 J223919.69+312904.5 339.832062 +31.484605 18.69 0.02 19.83 0.02 J223916.31+313047.2 339.817967 +31.513116 18.71 0.02 19.97 0.02 The photometry for AT2019rpn is based on the stars: Pan-STARRS_id RA Dec R(Lupton) err B(Lupton) err 153053199373132992 319,937282460 +37,543645500 15.64 0.01 16.79 0.01 153013199432441728 319,943228690 +37,509269790 17.25 0.01 18.50 0.01 153013199414348544 319,941391010 +37,514951160 17.04 0.01 18.44 0.01 153003199240135584 319,924010430 +37,504130480 16.52 0.01 17.89 0.01 153043199658230976 319,965800600 +37,533607760 16.10 0.01 17.57 0.01