TITLE: GCN CIRCULAR NUMBER: 15735 SUBJECT: GRB 140103A: AAO optical afterglow candidate DATE: 14/01/14 20:23:50 GMT FROM: Alexei Pozanenko at IKI, Moscow A. Volnova (IKI), R. Inasaridze (AAO), G. Inasaridze (AAO), V. Zhuzhunadze (AAO), Yu. Krugly (IA KhNU), I. Molotov (KIAM), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the optical counterpart of the Swift GRB 140103A (Mangano et al., GCN 15656) with AS-32 (0.7m) telescope of Abastumani Observatory on Jan. 3 and 4. We obtained several unfiltered images of 120 s exposure during each observational set. In the refined XRT position (Mangano, GCN 15666) we do not detect any object in stacked images. However we found a fading object which is not present in SDSS catalog. The coordinates of the obsjet is (J2000) RA=15 28 20.73, Dec = +37 45 28.8 with uncertainity of 0.3" in each coordinate. The position of the fading object is 5.2" from the refined XRT position (Mangano, GCN 15666). Due to fading nature of the new object we suggest it as an afterglow of the GRB 140103A. Details of the photometry is following: Date T_start t-t0, Filter Exp., OT err. (UT) mid, d s 2014-01-03 01:21:18 0.03953 None 5*120 21.14 0.12 2014-01-03 01:34:40 0.05345 None 10*120 21.35 0.12 2014-01-03 02:01:21 0.07662 None 15*120 21.41 0.11 2014-01-04 01:47:48 1.08483 None 34*120 >22.3 (3 sigma) The photometry is based on SDSS DR9 stars and gri -> R transformations (Lupton): N SDSS_id R(Lupton) 1 J152814.09+374706.3 18.20 2 J152819.83+374538.8 15.61 Finding chart and a light curve of the afterglow can be found in http://grb.rssi.ru/GRB140103A/grb140103A_chart.png and http://grb.rssi.ru/GRB140103A/grb140103A_lc.PNG