Аннотация
We show that the turbulent gas in the star-forming regions of galaxies is
unstable to wind formation via momentum deposition by radiation pressure or
other momentum sources like supernova explosions, even if the system is below
the average Eddington limit. This conclusion follows from the fact that the
critical momentum injection rate per unit mass for unbinding gas from a
self-gravitating system is proportional to the gas surface density and that a
turbulent medium presents a broad distribution of column densities to the
sources. For an average Eddington ratio of <Gamma> = 0.1 and for turbulent Mach
numbers greater than 30, we find that ~1% of the gas is ejected per dynamical
timescale at velocities larger than the local escape velocity. Because of the
lognormal shape of the surface density distribution, the mass loss rate is
highly sensitive to the average Eddington ratio, reaching 20-40% of the gas
mass per dynamical time for <Gamma> = 1. Implications for the efficiency of
star formation in giant molecular clouds are highlighted. Uncertainties are
discussed.
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