Polarimetry of binary stars


Abstract: Astronomical polarimetry is a powerful technique that can
provide physical information sometimes difficult or impossible to obtain
by any other type of observation. Almost every type of binary star can
benefit from polarimetric observations: pre-main-sequence objects, close
or contact binaries, mass-transfer systems, symbiotic stars, evolved
binaries, cataclysmic variables, eclipsing binaries, etc. In these
systems, polarimetry can help determine the geometry of the circumstellar
or circumbinary matter distribution, yield information on asymmetries and
anisotropies in these systems, identify obscured sources, map starspots,
detect magnetic fields, and establish orbital parameters. The orbital
inclination is a very important piece of information for a binary system
because it can lead to the determination of the components' masses, a
fundamental parameter that determines a star's structure and evolution.
This presentation will illustrate the usefulness of polarimetric
techniques for the study of binary stars.