Speaker
Description
Understanding what regulates star formation in galaxies is a fundamental question in astrophysics. However, a simple estimate of the star formation rate (SFR) that a galaxy like ours should have overpredicts the observed SFR by nearly two orders of magnitude. Over the past 50 years, three main explanations have been proposed to account for these low observed SFRs: magnetic fields, turbulence, and stellar feedback. While it is likely that all three mechanisms play some role, their relative contributions to regulating the SFR remain a subject of debate.
Stellar feedback appears to produce SFRs consistent with observations for Milky Way-type galaxies. However, it is far less clear whether stellar feedback alone can explain the SFR in gas-rich galaxies.
In this talk, I will present a new analytical model based on gravo-turbulent theory to compute the SFR. This model, which has been rigorously tested against a series of numerical simulations, includes turbulent dispersion and predicts that when the size of the system is smaller than the turbulent Jeans length, the SFR is significantly reduced.
This model, which can be used as a subgrid model in large-scale simulations that do not resolve the small-scale interstellar medium, provides a clear explanation of how turbulence, in conjunction with stellar feedback, may contribute to regulating star formation in galaxies.
