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29 June 2000 VLT FORS spectra of Be stars in the SMC cluster NGC 330
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We used FORS2 at UT2 of the VLT to obtain low resolution spectra of early type emission line stars in the field of the young open SMC cluster NGC 330. This cluster is known for its exceptional large number fraction of Be stars and could play a key role in constraining the Be phenomenon in general. 48 of the 59 program stars identified as H(alpha) excess sources by CCD imaging photometry can be confirmed to show H(alpha) line emission superimposed on a strong continuum. Comparison with VLT-FORS1 spectra collected a year earlier shows no or only a low significance of variability on the time scale of a year. To test the prediction of the hybrid model for global disk oscillations in Be star circumstellar disks we compared the number ratio of Be stars with asymmetric line profiles to the total number of Be stars with the known ratio of galactic field Be stars. About 10 of 47 emission line stars show asymmetric line profiles hence the theoretical prediction is not matched. We discuss several possibilities which might explain the discrepancy.
© (2000) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Wolfgang Hummel, Wolfgang Gaessler, Bernard Muschielok, Harald Schink, Harald E. Nicklas, Giancarlo Conti, Dario Maccagni, Stefan Keller, Karl-Heinz Mantel, Immo Appenzeller, Gero Rupprecht, Walter Seifert, Otmar Stahl, and Karl Tarantik "VLT FORS spectra of Be stars in the SMC cluster NGC 330", Proc. SPIE 4005, Discoveries and Research Prospects from 8- to 10-Meter-Class Telescopes, (29 June 2000);

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