The molecular gas and star formation in IRAS bright early-type disk galaxies. I - NGC 7625

Abstract

We present a detailed study of the distribution of the molecular and atomic gas and their relationships with the current star formation in NGC 7625, an Sa/S pec galaxy, using high-resolution images of Hα, 12 CO J=1→0, radio continuum and H I emission. Single-dish observations of 12 CO J=1→0 and 2→1 transitions were also used to evaluate, respectively, the missing interferometric CO flux and the CO excitation in the central 23″ of the galaxy. NGC 7625 contains ∼2.4×10 9 M ○. of molecular hydrogen, confined mostly to the central 3.5 kpc with peak H 2 surface density of 400 M ○. pc −2