Radiation Pressure Feedback in Galaxies

TL;DR

This paper investigates whether radiation pressure from starlight on dust can regulate star formation in galaxies by comparing observed luminosities to the dust Eddington limit, suggesting a potential feedback mechanism.

Contribution

It provides an analysis of radiation pressure as a feedback process in galaxies, highlighting the need for better constraints on dust and gas conversion factors.

Findings

Galaxies approach but do not significantly exceed the Eddington limit.

Many systems are below Eddington, possibly due to star formation intermittency.

Current data insufficient for definitive conclusions on radiation pressure feedback.

Abstract

We evaluate radiation pressure from starlight on dust as a feedback mechanism in star-forming galaxies by comparing the luminosity and flux of star-forming systems to the dust Eddington limit. The linear LFIR--L'HCN correlation provides evidence that galaxies may be regulated by radiation pressure feedback. We show that star-forming galaxies approach but do not dramatically exceed Eddington, but many systems are significantly below Eddington, perhaps due to the "intermittency" of star formation. Better constraints on the dust-to-gas ratio and the CO- and HCN-to-H2 conversion factors are needed to make a definitive assessment of radiation pressure as a feedback mechanism.