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We present B, V, R, and H alpha photometry of 8 clusters in the SmallMagellanic Cloud, 5 in the Large Magellanic Cloud, and 3 Galactic clusters, anduse 2 color diagrams (2-CDs) to identify candidate Be star populations in theseclusters. We find evidence that the Be phenomenon is enhanced in lowmetallicity environments, based on the observed fractional early-type candidateBe star content of clusters of age 10-25 Myr. Numerous candidate Be stars ofspectral types B0 to B5 were identified in clusters of age 5-8 Myr, challengingthe suggestion of Fabregat & Torrejon (2000) that classical Be stars shouldonly be found in clusters at least 10 Myr old. These results suggest that asignificant number of B-type stars must emerge onto the zero-age-main-sequenceas rapid rotators. We also detect an enhancement in the fractional content ofearly-type candidate Be stars in clusters of age 10-25 Myr, suggesting that theBe phenomenon does become more prevalent with evolutionary age. We brieflydiscuss the mechanisms which might contribute to such an evolutionary effect. Adiscussion of the limitations of utilizing the 2-CD technique to investigatethe role evolutionary age and/or metallicity play in the development of the Bephenomenon is offered, and we provide evidence that other B-type objects ofvery different nature, such as candidate Herbig Ae/Be stars may contaminate theclaimed detections of ``Be stars'' via 2-CDs.

astrophysical journal/the astrophysical journal

The Role of Evolutionary Age and Metallicity in the Formation of Classical Be Circumstellar Disks. I. New Candidate Be Stars in the LMC, SMC, and Milky Way