NON-AXISYMMETRICAL BE STAR CIRCUMSTELLAR DISKS

A new high resolution and high signal-to-noise ratio spectroscopic stu dy of H alpha, Fe II lambda 5317 and He I lambda 5876 emission lines o f northern and equatorial Be stars is presented. The line profiles are analyzed in order to test predictions of the recently proposed model of global disk oscillations. The Fe II and He I line profiles are used to derive the kinematics and the radial extension of the circumstella r disk-like plasma. Based on line profile derivatives, we present a ne w method, the separation of the inflection points (SIP), to resolve th e convolved peaks of H alpha winebottle-type profiles. The newly deriv ed peak positions are used to determine H alpha emission disk radii an d mean optical line depths along the line of sight. We find that these improved H alpha disk radii are smaller and closer to Fe Ir disk radi i than those H alpha disk radii derived from pure peak separations. We find evidence that class 2 profiles originate from quasi-Keplerian di sks with a non-axisymmetric density distribution.