Massive stars as a population and recent highlights on feedback effects
Sally Oey (University of Michigan)
The population of the most massive stars is responsible for driving major evolutionary processes
in star-forming galaxies through mechanical, radiative, and chemical feedback. Spatially
resolved studies of this stellar population yield simple parameterizations of clustering and
the stellar upper-mass limit. These lead to a straightforward analytic understanding of
resulting feedback processes, including a threshold star-formation rate above which galactic
superwinds shred the ISM, releasing ionizing radiation from the parent galaxies. Another
implication is a new paradigm for inhomogeneous galactic chemical evolution, which offers
an opposite extreme to the purely homogeneous Simple Model. Observations of
some Milky Way stellar populations will be examined.
