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We present a spectroscopic study of 150 Classical Be stars in 39 open clusters using medium resolution spectra in the wavelength range 3800 - 9000 AA. One-third of the sample (48 stars in 18 clusters) has been studied for the first time. All these candidates were identified from an extensive survey of emission stars in young open clusters using slitless spectroscopy (Mathew et al. 2008). This large data set covers CBe stars of various spectral types and ages found in different cluster environments in largely northern open clusters, and is used to study the spectral characteristics of CBe stars in cluster environments. About 80% of CBe stars in our sample have H-alpha equivalent width in the range -1 to -40 AA. About 86% of the surveyed CBe stars show Fe II lines. The prominent Fe II lines in our surveyed stars are 4584, 5018, 5169, 5316, 6318, 6384, 7513 and 7712 AA. We have identified short and long-term line profile variability in some candidate stars through repeated observations.
In this study, we analyze the emission lines of different species present in 118 Galactic field classical Be stars in the wavelength range of 3800 - 9000 AA. We re-estimated the extinction parameter (A$_V$) for our sample stars using the newly availa
We present FEROS high-resolution (R~45000) optical spectroscopy of 34 Herbig Ae/Be star candidates with previously unknown or poorly constrained spectral types. Within the sample, 16 sources are positionally coincident with nearby (d<250 pc) star-for
Rapid rotation is a fundamental characteristic of classical Be stars and a crucial property allowing for the formation of their circumstellar disks. Past evolution in a mass and angular momentum transferring binary system offers a plausible solution
We present the results of a multiplicity survey for a magnitude-limited sample of 31 classical Be stars conducted with the Navy Precision Optical Interferometer and the Mark III Stellar Interferometer. The interferometric observations were used to de
Star clusters are privileged laboratories for studying the evolution of massive stars (OB stars). One particularly interesting question concerns the phases, during which the classical Be stars occur, which unlike HAe/Be stars, are not pre-main sequen