A Useful Approximation for Computing the Continuum Polarization of Be Stars

This paper describes a practical model for the polarization of Be stars whichcan be used to estimate roughly the physical parameters for optically thincircumstellar envelopes from broadband UBVRI photopolarimetry data. Analysis oflong-term variability in terms of these parameters is a promising approachtoward understanding the Be phenomenon. An interesting result from fitting themodel to observations of eight Be stars is that all of them may havegeometrically thin disks, with opening half-angles on the order of ten degreesor less. This contributes to the growing evidence that most Be disks aregeometrically thin.Comment: 20 pages including 12 figures, LaTeX2e+AASTeX5.0, accepted by The Astrophysical Journa