Spectroscopic eclipse mapping of mass-accreting Algol-type stars with pulsating components

• Applicant: Dr. Holger Lehmann
• Subject Area: Astrophysics and Astronomy
• Term: from 2007 to 2011
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 43516563

We want to investigate mass-accreting Algol-type systems with pulsating components by using time series of high-resolution spectra. From the analysis of spectral line profile variations observed over the full orbital period including eclipses we want to extract information on global stellar parameters of the components as well as on the pulsations of the primaries. We want to establish a code that computes synthetic stellar line profiles of eclipsing binaries observed in disk-integrated light. Stellar parameters will be derived by adjusting the corresponding model parameters like rotation velocity, inclinations of rotation and orbital axes, stellar radii, limb darkening, and parameters of the stellar atmospheres to fit the observations. During eclipses, the pulsating components of Algol-type systems show amplitude and phase modulations of the non-radial pulsation modes. These modulations are due to the screening effect caused by the eclipsing component. Our method models this screening using the full information content of spectral lines. We want to include the calculation of non-radial pulsation modes into our model and try to use it for a mode identification by eclipse mapping. Results will be compared to seismologic models of the stars.

• DFG Programme: Research Grants