The C and CO lines in nearby galaxies: The cooling of the interstellar medium

We observed four galaxy nuclei (IC 10, IC 342, M 83 and NGC 6946) with the Caltech Submillimeter Observatory in the P-3(2)-P-3(1) fine structure transition of atomic carbon [CI] at 809 GHz (for IC 10 and IC 342), and in the rotational lines of carbon monoxide (CO)-C-12(J=2-1) (for IC 10, M 83 and NGC 6946), (J=3-2), (J=4-3), (J=6-5) (for IC 10, IC 342, M 83 and NGC 6946), (J=7-6) (for IC 10 and IC 342) and (CO)-C-13(J=3-2) (for M 83 and NGC 6946). The present multitransition study is the most complete to date for these galaxies. These results, combined with our previous work on Henize 2-10 and NGC 253 (Bayet et al. 2004) are discussed for comparing the physical properties of the warm and dense interstellar medium in galaxy nuclei. This study provide us template for more distant galaxies and be naturally included in large scientific programs developed with future instruments as ALMA and Herschel/HIFI,PACS..