Astronomy in the catacombs: stars with special peculiarities as members of open clusters

Abstract

The emission-line Of-, WR- and Be-type stars as members of open clusters are analyzed in particular related to their photometric data. It is found that amont the high-luminosity objects, the Of stars are the more common stars among the brightest members of open clusters. About 10% to 30% of the WR stars are members of open clusters. Those clusters with Of stars have much brighter apparent magnitude stars than those with WR-type stars. Concerning the Be stars, mostly are situated away of the main sequence; their color excesses E(B-V) of the circumstellar envelope is up to 0.3 magnitudes in extreme cases.