Infrared photometry of the dwarf nova V2051 Ophiuchi: I - The mass donor star and the distance

Abstract

We report the analysis of time-series of infrared $JH{K}_s$ photometry of the dwarf nova V2051 Oph in quiescence. We modelled the ellipsoidal variations caused by the distorted mass-donor star to infer its $JH{K}_s$ fluxes. From its infrared colors we estimate a spectral type of $M(8.0\pm 1.5)$ and an equivalent blackbody temperature of $T_{\mathrm{BB}}=(2700\pm 270)K$. We used the Barnes & Evans relation to infer a photometric parallax distance of $d_{\mathrm{BE}}=(102\pm 16)$ pc to the binary. At this short distance, the corresponding accretion disc temperatures in outburst are too low to be explained by the disc-instability model for dwarf nova outbursts, underscoring a previous suggestion that the outbursts of this binary are powered by mass-transfer bursts.

5 pages, 2 figures

References in corpus (4)

• The Donor Stars of Cataclysmic Variables
• Barnes-Evans relations for dwarfs with an application to the determination of distances to cataclysmic variables
• A study of the evolution of the accretion disk of V2051 Oph through two outburst cycles
• A multicolor near-infrared study of the dwarf nova IP Peg

Cited by in corpus (1)

• Infrared photometry of the dwarf nova V2051 Ophiuchi: II -- The quiescent accretion disc and its spiral arms