Dust Eddington ratios for star-forming galaxy subregions

Radiation pressure on dust is an important feedback process around star clusters and may eject gas from bright sub-regions in star-forming galaxies. The Eddington ratio has previously been constructed for galaxy-averaged observations, individual clusters, Galactic HII regions. Here we assess the role of radiation thousands across two local galaxies, NGC 6946 5194. Using a model spectral energy distribution stellar population synthesis realistic grain scattering absorption, compute flux- pressure-mean opacities population-averaged optical depth $\langle\tau_{\rm RP}\rangle$. Monte-Carlo calculations, momentum coupling through dusty column to continuum. Optically-thin regions young populations are $30-50$ times super-Eddington. We calculate including mass old stars HI molecular gas. fraction total formation that currently super-Eddington, provide assessment dynamics. Depending assumed height age population, find $\sim0-10$% sightlines These be accelerated $\sim5-15$ km/s by alone. Additionally, our results show beamed function $1-\exp(-\langle\tau_{\rm RP}\rangle)$ excellent approximation transfer. Opacities depths tabulated SEDs different ages continuous formation.