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We obtained photometric observations of the nova-like cataclysmic variable RW Tri and gathered all available AAVSO and other data from the literature. We determined the system parameters and found their uncertainties using the code developed by us to model the light curves of binary systems. New time-resolved optical spectroscopic observations of RW Tri were also obtained to study the properties of emission features produced by the system. The usual interpretation of the single-peaked emission lines in nova-like systems is related to the bi-conical wind from the accretion discs inner part. However, we found that the Halpha emission profile is comprised of two components with different widths. We argue that the narrow component originates from the irradiated surface of the secondary, while the broader components source is an extended, low-velocity region in the outskirts of the accretion disc, located opposite to the collision point of the accretion stream and the disc. It appears to be a common feature for long-period nova-like systems -- a point we discuss.
New time-resolved optical spectroscopic echelle observations of the nova-like cataclysmic variable RW Sextantis were obtained, with the aim to study the properties of emission features in the system. The profile of the H_alpha emission line can be cl
The morphology and optical spectrum of IPHASXJ210205+471015, a nebula classified as a possible planetary nebula, are however strikingly similar to those of ATCnc, a classical nova shell around a dwarf nova. To investigate its true nature, we have obt
We present a study of the orbital light curves of the recurrent nova IM Normae since its 2002 outburst. The broad eclipses recur with a 2.46 hour period, which increases on a timescale of 1.28(16)x10^6 years. Under the assumption of conservative mass
We report on the detection of the linear rms-flux relation in two accreting white dwarf binary systems: V1504 Cyg and KIC 8751494. The rms-flux relation relates the absolute root-mean-square (rms) variability of the light curve to its mean flux. The
We report simultaneous observations of the flaring behaviour of the cataclysmic variable star AE Aqr. The observations are in Johnson B and V bands. The colour-magnitude diagrams (B-V versus V and B-V vs. B) show that the star becomes blues as it bec