Near-simultaneous spectroscopic and broadband polarimetric observations of Be stars.
GHOSH K., IYENGAR K.V.K., RAMSEY B.D. and AUSTIN R.A.
Abstract (from CDS):
Near simultaneous optical spectroscopic (on four nights) and broadband linear continuum (B, V, R, and I bands) polarimetric (on seven nights) observations of 29 Be stars were carried out during 1993November-December. The program Be stars displayed wavelength dependence of intrinsic polarizations with no frequency dependence of polarimetric position angles. Some of the Be stars displayed long-term polarization variability. The Be and Be-shell stars could not be distinguished from one another solely on the basis of their polarization values. Full widths at half-maximum of the Hα profiles and the intrinsic linear continuum polarizations are closely correlated with the projected rotational velocities of the program stars. Photospheric-absorption-corrected equivalent widths of Hα profiles [W(α)] and the radii of Hα-emitting or -absorbing envelopes (Re or R_a_) are nonlinearly correlated with the intrinsic continuum polarizations of these stars. However, W(α) and Re are linearly correlated. With large uncertainties, there is a trend of spectral dependence of polarization. Detailed discussion of these results is presented in this paper.Key words: