Central Bureau Electronic Telegrams, 697, 1 (2006/October-0)
WORTERS H.L., EYRES S.P.S., BROMAGE G.E. and OSBORNE J.P.
Abstract (from CDS):
H. L. Worters, S. P. S. Eyres, G. E. Bromage, University of Central Lancashire; and J. P. Osborne, University of Leicester, report the reappearance of optical flickering in the recurrent nova RS Oph. Subsequent to notification of rebrightening at 208 days after the latest outburst (IAUC 8761), RS Oph was monitored for up to 2 hours with 30-s time resolution on 12 nights between Oct. 11 and 24, using the 1-m South African Astronomical Observatory (SAAO) telescope with the SAAO CCD. Differential V-band photometry indicates flickering with an amplitude of 0.1-0.2 mag on timescales of 500-1000 s (compared to variation of comparison stars in the field of 0.02 mag). An overall decline in brightness was also recorded over the duration of these observations, from a mean magnitude value of V about 11.2 on Oct. 11.77 UT (day 241 after outburst) to V = 11.9 on Oct. 24.71 (day 254). Sample results of the V-band photometry are as follows: Oct. 11.77, amplitude 0.05 mag, mean V about 11.2; 19.75, 0.06, 11.5; 23.75, 0.1, 11.8. B-band photometry on Oct. 17.75 reveals an amplitude of 0.06 mag and a mean B magnitude of about 13.2. On day 117 after outburst, flickering was not observed at amplitudes above 0.03 mag (http://www.astronomerstelegram.org/?read=832), suggesting that accretion has reestablished in the last 124 days.