On the global triggering mechanism of star formation in galaxies

TL;DR

This paper investigates how large-scale gravitational and dynamical processes trigger star formation in galaxies, revealing a strong correlation between a specific mass scale and star formation rates across diverse galaxy types.

Contribution

It introduces a new relation linking the largest unstable mass scale in rotating galaxies to their star formation rates, grounded in stability thresholds and turbulence effects.

Findings

Largest unstable mass scale correlates with star formation rate.

Derived relation explains the link between star formation and brightest stellar clusters.

Supports the role of dynamical stability and turbulence in star formation regulation.

Abstract

We study the large-scale triggering of star formation in galaxies. We find that the largest mass-scale not stabilized by rotation, a well defined quantity in a rotating system and with clear dynamical meaning, strongly correlates with the star formation rate in a wide range of galaxies. We find that this relation can be explained in terms of the threshold for stability and the amount of turbulence allowed to sustain the system in equilibrium. Using this relation we also derived the observed correlation between the star formation rate and the luminosity of the brightest young stellar cluster.