Astron. Astrophys. Suppl. Ser. 137, 21-41

The ionising cluster of 30 Doradus

II. Spectral classification for 175 stars

G. Bosch¹ - R. Terlevich¹ - J. Melnick² - F. Selman²

Send offprint request: gbosch@ast.cam.ac.uk

1 - Institute of Astronomy, Madingley Road, Cambridge CB3 0HA, UK
2 - European Southern Observatory, Alonso de Córdova 3107, Santiago, Chile

Received September 16, 1998; accepted February 5, 1999

Abstract:

We present spectral types for 175 stars in the ionising cluster of 30 Doradus derived from multislit observations of 231 stars. Comparison with published classifications for 70 stars in common with other authors reveals excellent agreement with the exception of a few cases which are discussed in detail. Our new observations raise to 261 the total number of stars in 30 Dor with known spectral types, outside R136. We analyse the spatial distribution of these stars according to their spectral types, and find evidence for mass segregation.

Key words: stars: Hertzsprung Russell (HR) diagram -- stars: luminosity function, mass function -- stars: early-type -- ISM: dust, extinction -- galaxy: open clusters and associations: general -- galaxies: Magellanic Clouds