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Description
We present time-resolved photometry of five relatively poorly-studied cataclysmic variables: V1193 Ori, LQ Peg, LD 317, V795 Her and MCT 2347-3144. The observations were made using four 1m-class telescopes for a total of more than 250h of observation and almost 16,000 data points. For LQ Peg WHT spectroscopic data have been analysed as well. The light curves show a whole range of variability on different time scales, from minutes to months. We detect for the first time a brightness variation of 0.05mag in amplitude in V1193 Ori on the same timescale as the orbital period, that we interpret as the result of the irradiation of the secondary. A 20-min Quasi-Periodic Oscillation is also detected. The mean brightness of the system has changed by 0.5mag on a three month interval, while the flickering was halved. In LQ Peg a 0.05mag modulation was revealed with a period of about 3h. The flickering was much smaller, of the order of 0.025mag. A possible Quasi-Periodic Oscillation could exist near 30min. For this object, the WHT spectra are single peaked and do not show any radial-velocity variations. The data of LD 317 show a decrease in the mean magnitude of the system. No periodic signal was detected but this is certainly attributable to the very large flickering observed: between 0.07 and 0.1mag. For V795 Her, the 2.8-hour modulation, thought to be a superhump arising from the precession of the disc, is present. We show this modulation not to be stable in terms of periodicity, amplitude and phase. Finally, for MCT 2347-3144, a clear modulation is seen in a first dataset obtained in October 2002. This modulation is absent in August 2003, when the system was brighter and showed much more flickering.
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