Doppler Tomography and Photometry of the Cataclysmic Variable 1RXS J064434.5+334451

Abstract

We have obtained simultaneous photometric and spectroscopic observations of the cataclysmic variable 1RXS J064434.5+334451. We have calibrated the spectra for slit losses using the simultaneous photometry allowing to construct reliable Doppler images from H$\alpha$ and HeII 4686 emission lines. We have improved the ephemeris of the object based on new photometric eclipse timings, obtaining $HJD=2453403.759533+0.26937446E$. Some eclipses present a clear internal structure which we attribute to a central HeII emission region surrounding the white dwarf, a finding supported by the Doppler tomography. This indicates that the system has a large inclination angle $i=78\pm 2^{\circ }$. We have also analysed the radial velocity curve from the emission lines to measure its semi--amplitude, $K_1$, from H$\alpha$ and HeII 4686 and derive the masses of the components: $M_1=0.82\pm 0.06$ M${}_{\odot }$, $M_2=0.78\pm 0.04$ M${}_{\odot }$ and their separation $a=2.01\pm 0.06$ $R_{\odot }$. The Doppler tomography and other observed features in this nova-like system strongly suggests that this is a SW Sex-type system.

11 pages, 10 figures, accepted for publication in MNRAS

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• The Donor Stars of Cataclysmic Variables
• Deep MMT Transit Survey of the Open Cluster M37 II: Variable Stars
• SW Sextantis stars: the dominant population of CVs with orbital periods between 3-4 hours
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Cited by in corpus (4)

• The structure of accretion flows in nova-like cataclysmic variables: RW Sextantis and 1RXS J064434.5+334451
• Structure of accretion flows in the nova-like cataclysmic variable RW Tri
• BG Tri an example of a low inclination RW Sex-type novalike
• New radial velocity observations of AH Her: evidence for material outside the tidal radius