Optical characterization of two cataclysmic variables: RBS 0490 and SDSS J075939.79+191417.3

TL;DR

This study provides detailed optical observations of two cataclysmic variables, determining their orbital periods, eclipse features, and spectral characteristics, thereby enhancing understanding of their accretion processes and magnetic properties.

Contribution

The paper offers refined orbital periods, eclipse analysis, and spectral features for RBS 0490 and SDSS J075939.79+191417.3, distinguishing their magnetic properties and accretion structures.

Findings

RBS 0490 has an orbital period of 1.689 hours.

SDSS J075939.79+191417.3 has an orbital period of 3.1424 hours.

SDSS J075939.79+191417.3 shows eclipse features indicating an accretion disc.

Abstract

We present optical photometric and spectroscopic observations of two Cataclysmic Variables (CVs), namely RBS 0490 and SDSS J075939.79+191417.3. The optical variations of RBS 0490 have been found to occur at the period of 1.689$\pm$0.001 hr which appears to be a probable orbital period of the system. Present photometric observations of SDSS J075939.79+191417.3 confirm and refine the previously determined orbital period as 3.14240928$\pm$0.00000096 hr. The presence of long-duration eclipse features in the light curves of SDSS J075939.79+191417.3 indicates eclipses might be due to an accretion disc and bright spot. The orbital inclination of SDSS J075939.79+191417.3 is estimated to be $\sim$ 78 $^\circ$ using the eclipse morphology. The phased-light curve variations during the orbital cycle of RBS 0490 provide evidence of the emission from an independent second accretion region or a second fainter pole. Optical spectra of RBS 0490 and SDSS J075939.79+191417.3 show the presence of strong Balmer, weak He II ($\lambda$4686) emission lines, along with the detection of strong $H\beta$ emission lines with a large value of equivalent width. The characteristic features of RBS 0490 seem to favour low-field polars, while SDSS J075939.79+191417.3 appears to be similar to the non-magnetic systems.