Pressure-regulated, Feedback-modulated Star Formation in Disk Galaxies

The star formation rate (SFR) in galactic disks depends on both the quantity of available interstellar medium (ISM) gas and its physical state. Conversely, ISM's state SFR, because "feedback" energy momentum injected by recently-formed massive stars is crucial to offsetting losses from turbulent dissipation radiative cooling. also responds gravitational field that confines it, with increased weight driving higher pressure. In a quasi-steady state, it expected mean total pressure different thermal phases will match each other, component pressures satisfy dynamical equilibrium requirements, SFR adjust as needed provide requisite stellar radiation supernova feedback. pressure-regulated, feedback-modulated (PRFM) theory star-forming ISM formalizes these ideas, leading prediction per unit area, Sigma_SFR, scale nearly linearly W. terms large-scale surface density Sigma, plus dark matter rho_sd, effective velocity dispersion sigma_eff, an observable estimator W~P_DE=pi G Sigma^2/2+Sigma(2G rho_sd)^{1/2} this predicted midplane P_tot. Using suite multiphase magnetohydrodynamic simulations run TIGRESS computational framework, we test principles PRFM model calibrate feedback yield Upsilon_tot = P_tot/Sigma_SFR ~ 1000 km/s, well components. We compare results theory, previous numerical simulations, observations, finding excellent agreement.