Next: Introduction
A Reconnaissance of the 900--1200 Å Spectra of
Early O Stars in the Magellanic Clouds
Nolan R. Walborn and Knox S. Long
Space Telescope Science Institute,
3700 San Martin Drive, Baltimore, MD 21218
Daniel J. Lennon and Rolf-Peter Kudritzki
Institute for Astronomy and Astrophysics, Munich University,
Scheinerstrasse 1, D-81679 Munich, Germany
Abstract:
The first survey of the far-UV (900--1200 Å) spectra of O stars in
the Magellanic Clouds, observed with the Hopkins Ultraviolet
Telescope during the Astro-2 mission, is presented. Five objects in
each Cloud were obtained, including four of type O3 (one of which is
the current candidate for the most massive star known) and a pair of
O4 If supergiants with remarkably different relative CNO strengths.
All of the SMC objects are in its largest H II region, NGC 346, and
show strong effects of the systemic metal deficiency. The
systematic spectral-type dependence of the numerous stellar-wind
features in this relatively little-studied wavelength range,
including those of O VI and S VI, is illustrated and described.
One of the LMC O3 stars, with 
, displays strong
interstellar H
features.
Subject headings: Magellanic Clouds --- stars: abundances --- stars:
early-type --- stars: mass-loss --- ultraviolet: stars
walborn@stsci.edu