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On Be Star Candidates and Possible Blue Pre-Main Sequence Objects in the Small Magellanic Cloud

R. E. Mennickent·G. Pietrzynski·W. Gieren·O. Szewczyk
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Abstract

Recently the OGLE experiment has provided accurate light curves and colours for about 2 millions stars in the Small Magellanic Cloud. We have examined this database for its content of Be stars, applying some selection criteria, and we have found a sample of $\sim$ 1000 candidates. Some of these stars show beautiful light curves with amazing variations never observed in any Galactic variable. We find outbursts in 13% of the sample (Type-1 stars), high and low states in 15%, periodic variations in 7%, and the usual variations seen in Galactic Be stars in 65% of the cases. The Galactic counterparts of Type-1 objects could be the outbursting Be stars found by Hubert & Floquet (1998) after the analysis of Hipparcos photometry. We discuss the possibility that Type-1 stars could correspond to Be stars with accreting white dwarf companions or alternatively, blue pre-main sequence stars surrounded by thermally unstable accretion disks. We provide coordinates and basic photometric information for these stars and some examples of light curves.

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R. E. Mennickent, G. Pietrzynski, W. Gieren, O. Szewczyk. 2002-06-19. On Be Star Candidates and Possible Blue Pre-Main Sequence Objects in the Small Magellanic Cloud. https://doi.org/10.1051/0004-6361%3A20020916

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