The Local Group as an Astrophysical Laboratory for
Massive Star Feedback (Review)
M.S. Oey
The feedback effects of massive stars on their galactic and
intergalactic environments can dominate evolutionary processes in
galaxies and affect cosmic structure in the Universe. Only the Local
Group offers the spatial resolution to quantitatively study feedback
processes on a variety of scales. Lyman continuum
radiation from hot, luminous stars ionizes \hii\ regions and is
believed to dominate production of the warm component of the
interstellar medium (ISM). Some of this radiation apparently escapes from
galaxies into the intergalactic environment. Supernovae and strong
stellar winds generate shell structures such as supernova remnants,
stellar wind bubbles, and superbubbles around OB associations. Hot
($10^6$ K) gas is generated within these shells, and is believed to be
the origin of the hot component of the ISM. Superbubble activity thus
is likely to dominate the ISM structure, kinematics, and phase balance
in star-forming galaxies. Galactic superwinds in starburst galaxies
enable the escape of mass, ionizing radiation, and heavy elements.
Although many important issues remain to be resolved, there is little
doubt that feedback processes plays a fundamental role in energy cycles on
scales ranging from individual stars to cosmic structure. This
contribution reviews studies of radiative and mechanical feedback in
the Local Group.
2003, in The Local Group as an Astrophysical Laboratory,
eds. M. Livio et al.,
(Cambridge: Cambridge U. Press), in press.
PostScript preprint
astro-ph/0307131
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