Regulation of star formation by large-scale gravitoturbulence

A simple model for star formation based on supernova (SN) feedback and gravitational heating via the collapse of perturbations in gravitationally unstable disks reproduces Schmidt-Kennicutt relation between rate (SFR) per unit area, $\Sigma_{SFR}$, gas surface density, $\Sigma_g$, remarkably well. The velocity dispersion, $\sigma_g$, is derived self-consistently conjunction with $\Sigma_{SFR}$ found to match observations. Gravitational instability triggers {"gravito-turbulence"} at scale least stable perturbation mode, boosting $\sigma_g$ $\Sigma_g> \, \Sigma_g^\textrm{thr}=50\, {\rm M}_\odot\, pc}^{-2}$, contributing pressure needed carry disk weight vertically. reduced observed level $ \Sigma_g > \Sigma_g^\textrm{thr}$, whereas lower densities, SN prevailing energy source. Our proposed recipes require efficiencies order 1\%, Toomre parameter, $Q$, joint gaseous stellar predicted be close critical value marginal stability $\Sigma_g< spreading values larger dispersion higher $\Sigma_g$.