New Spectroscopic Data of Luminous Peculiar B-Type Stars

Abstract

Since a long our group have been analysing the physical properties of some peculiar southern Be stars (see e.g. Freitas Pacheco et al., 1985; Lopes et al., 1992; Araújo and Freitas Pacheco, 1994). These stars share several common characteristics as an optical spectra dominated by Balmer and FeII emission lines (often displaying P Cygni profiles) and absorption lines of FeII and other low ionization species in the UV. Besides, prominent emissions are usually seen in the near IR and some of them are IRAS sources. Recently we have started a new study program on them, with the following goals:

• i-) to obtain new, high-quality data of such objects

• ii-) to perform the fitting of some lines (Hα, Hβ, HeI λ 5876 Å) employing a numerical code developped by one of us (M.A.M.)

• iii-) to estimate mass-loss rates and velocity fields, on the basis of the line profile fittings.

• iv-) to analyse the radiative force acting on them, using a hydrodynamical code (Araújo, 1995.

• v-) to try to clarify the evolutionary status of them and their relationship with other stellar classes (for instance LBVs).