Efficacy of early stellar feedback in low gas surface density environments

Understand

We present a suite of high resolution radiation hydrodynamic simulations of a small patch ($1 \ {\rm kpc}^2$) of the inter-stellar medium (ISM) performed with Arepo-RT, with the aim to quantify the efficacy of various feedback processes like supernovae explosions (SNe), photoheating and radiation pressure in low gas surface density galaxies ($\Sigma_{\rm gas} \simeq 10 \ {\rm M}_\odot \ {\rm pc}^{-2}$).

• We show that radiation fields decrease the star formation rate and therefore the total stellar mass formed by a factor of $\sim 2$.
• This increases the gas depletion timescale and brings the simulated Kennicutt-Schmidt relation closer to the observational estimates.
• Radiation feedback coupled with SNe is more efficient at driving outflows with the mass and energy loading increasing by a factor of $\sim 10$.