EELOs: Can We Define a Galactic B[e] Group?

Abstract

The class of B[e] stars is a spectroscopically defined group from which members can be identified as LBVs, supergiants, symbiotics, post-AGB, proto-planetary and young stars. Objects that cannot be classified as such are frequently designated to be a special stellar class with an unidentified (evolutionary) status. To investigate if such a new stellar B[e] class holds an homogeneous stellar population we have searched for galactic B[e] stars among; several samples of EELOs.

Based on the spectral definition alone, we find 31 B[e] stars and 18 candidates that are unclassified. We argue that most of these objects could be member of the classes mentioned when properly characterized and their astrophysical properties are better determined. We find only a few objects that are well studied and could not be classified. On statistical and evolutionary grounds we argue that these objects will end up in one of the known classes leaving no further arguments to define new classes of B[e] stars. Based on these results, we show and propose a new classification scheme for B[e] stars.