Stellar Parameters of Short Period Pulsators in Eclipsing Systems

Doug Hoffman

Short period pulsating stars (Delta Scuti and RR Lyr type) are rather common, though the details of their pulsation, mass, and radius are largely unknown. By finding and analyzing eclipsing pulsators, the masses and radii of these objects can be derived and will help constrain models. It is also largely unknown whether a companion star can alter the pulsational properties of these objects. My thesis will answer these questions and consists of two main parts.

The first is discovering and identifying eclipsing pulsators for study. There are currently only 26 known short period eclipsing pulsators. Eleven of these were discovered by the All Sky Automated Survey (ASAS) in the southern hemisphere. The rest were discovered by searching known eclipsing systems in both hemispheres. I plan on using a very similar database, the Robotic Optical Transient Search Experiment (ROTSE-I) to search the northern hemisphere. Other databases will be used as well to aid in the search. An automated identification and classification of variable objects scheme will be employed to perform the search. This scheme will be a major part of the project and can be used on a variety of current and upcoming large astronomical databases.

The second part is scouring the eclipsing systems discovered for a pulsating component and then analyzing them. By subtracting off the oscillations due to the eclipse and performing Fourier analysis, pulsating components can be identified. Follow-up observations can then be used to aid in the determination of stellar parameters. I estimate that around 15 new eclipsing pulsators will be found in the ROTSE-I database alone.