Molecules in Galaxies IV. Molecular Hydrogen, Atomic Hydrogen and Dust in Virgo Cluster Galaxies.
01 January 1987
If gas and dust are well-mixed in a galaxy, the dust mass should be proportional to the sum of the masses of atomic and molecular gas. This assumption has been used to estimate the mean conversion ratio between the flux in the CO J = 1-0 line and the molecular gas mass of a galaxy using a set of observations of the 100microns continuum flux density, the HI 21 cm line flux and the CO line flux for a sample of spiral galaxies in the Virgo Cluster; these galaxies have a wide variation in the ratio of CO to HI line flux. The result, N(H sub 2) = 6.3 +- 3.5 x 10 sup 20 mol cm sup (-2) (tau sub alpha * delta V) is in agreement with values inferred from observations of the molecular interstellar medium in the Galaxy.