Atmospheric pressure and molecular cloud formation in early-type galaxies

TL;DR

This paper investigates how atmospheric pressure influences molecular cloud formation in early-type galaxies, revealing a strong correlation that suggests hot atmospheres facilitate the conversion of atomic to molecular hydrogen.

Contribution

It provides observational evidence linking atmospheric pressure to molecular gas mass in early-type galaxies, highlighting pressure's role in molecular cloud formation.

Findings

Strong correlation between atmospheric pressure and molecular gas mass.

Ambient pressure influences atomic to molecular hydrogen conversion.

Data supports hot atmospheres as sites for molecular cloud condensation.

Abstract

A strong correlation between atmospheric pressure and molecular gas mass is found in central cluster galaxies and early-type galaxies. This trend and a similar trend with atmospheric gas density would naturally arise if the molecular clouds condensed from hot atmospheres. Limits on the ratio of molecular to atomic hydrogen in these systems exceed unity. The data are consistent with ambient pressure being a significant factor in the rapid conversion of atomic hydrogen into molecules as found in normal spiral galaxies.