Research

Publications, Astronomy links
Short description (at some point to include links to more info)
I am mainly working on Cataclysmic Variables (CVs). These are close interacting binary stars, with the primary component (the more massive one) being a white dwarf, and the secondary component usually being a late-type (K-M) star, that is on, or at least close to, the main-sequence. The latter star transfers matter via Roche-lobe overflow into the gravitational regime of the primary star. Depending on the strength of the white dwarf's magnetic field, this matter is accreted by the primary either via an accretion disc, or via accretion columns that form along the magnetic field lines (in case of a strong field).
Photometrically, these systems show a wide range of variability, both on long-term (weeks to hundreds of years) and short-term (seconds to hours) time scales. Their spectral appearance depends on the individual strength of the three components: the white dwarf (broad Balmer absorption and blue continuum), the red star (molecular absorption and red continuum), and the accretion disc (Balmer and He emission lines and a flat, blue continuum). All lines undergo Doppler shifting that is modulated with the orbital period (roughly between 80 min to 10 h).
My specific research interests concern (in no particular order):