Disk Growth and Quenching

TL;DR

This paper proposes that disk quenching occurs when incoming gas has excessive angular momentum, preventing the radial inflow needed for sustained star formation, supported by observational evidence and future validation prospects.

Contribution

It introduces a novel angular momentum-based mechanism for star formation quenching in galactic disks, linking inflow properties to star formation cessation.

Findings

Angular momentum of inflowing gas increases with galaxy growth.

High angular momentum inflow can halt the radial gas flow necessary for star formation.

Observational evidence supports the angular momentum quenching scenario.

Abstract

Based on well established scaling relation for star forming galaxies as a function of redshift, we argue that the implied growth by a large factor of their angular momentum requires that the angular momentum of the inflowing gas fuelling star formation and disk growth must also secularly increase. We then propose that star formation in disks can cease (quench) once the accreted material (mainly atomic hydrogen) comes in with excessive angular momentum for sustaining an adequate radial flow of cold, molecular gas. Existing observational evidence supporting this scenario is mentioned, together with some future observational studies that may validate (or invalidate) it.