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arXiv · 2203.17198

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

Arti Joshi·J. C. Pandey·Nikita Rawat·Ashish Raj·Wei Wang·H. P. Singh
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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.

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Arti Joshi, J. C. Pandey, Nikita Rawat, Ashish Raj, Wei Wang, H. P. Singh. 2022-03-31. Optical characterization of two cataclysmic variables: RBS 0490 and SDSS J075939.79+191417.3. https://doi.org/10.3847/1538-3881%2Fac6026

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