TITLE: GCN CIRCULAR NUMBER: 7239 SUBJECT: X-ray transient in NGC 2770: RTT150 optical observations DATE: 08/01/30 16:25:52 GMT FROM: Irek Khamitov at TUG I. Khamitov (TUG), I. Bikmaev, R. Gumerov, A. Nemtinov, N. Sakhibullin (KSU/AST), R. Burenin, M. Pavlinsky, R. Sunyaev (IKI), Z. Eker (TUG), U. Kiziloglu (METU), E. Gogus (Sabanci Uni.) report: We continued observations of the optical counterpart to X-ray transient in NGC 2770, SN2008D (GCN Rep. 110.1, GCN Circ. 7160, 7161) with Russian-Turkish 1.5-m telescope (RTT150, Bakirlitepe, TUBITAK National Observatory, Turkey) in 26 (02:50-04:50UT), 27 (01:00-04:00UT), 28 (04:05UT) Jan 2008 using ANDOR TE CCD (DW-436). Series of BVRI direct images were taken on Jan 26 and 27, and also we made 300s R-exposure on Jan 28 under windy weather conditions (the seeing was more then 2 arcsec for all observations). The object shows no variability between the nignts at the level >~ 0.05mag. In comparision with the our previous observations (11, 12 Jan, Bikmaev et al., GCN7206) the OT is brighter approximatelly by 1.0 mag and 0.6 mag in R and B bands respectively. Assuming R=17.3 and B=17.7 magnitudes for USNO-A2.0 1200-06240802 star, we estimate the following magnitudes for the transient: Time, UT t-t0,days mag Jan 26.14 16.58 R = 17.03 Jan 26.15 16.59 B = 18.06 Jan 27.09 17.53 B = 18.13 Jan 27.12 17.56 R = 17.01 Jan 28.17 18.61 R = 16.98 Also we found that in our previous circular there was a misprint in t-t0 column. The correct t-t0 values can be obtained by adding one day to the values in that circular. -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean.