An empirical determination of the dust mass absorption coefficient, Κd, using the herschel reference survey

Abstract

We use the published photometry and spectroscopy of 22 galaxies in the Herschel Reference Survey to determine that the value of the dust mass absorption coefficient Κd at a wavelength of 500 μm is Κ500 = 0.051+0.070-0.026 m2 kg-1. We do so by taking advantage of the fact that the dust-to-metals ratio in the interstellar medium of galaxies appears to be constant. We argue that our value for Κd supersedes that of James et al. - who pioneered this approach for determining Κd - because we take advantage of superior data, and account for a number of significant systematic effects that they did not consider. We comprehensively incorporate all methodological and observational contributions to establish the uncertainty on our value, which represents a marked improvement on the oft-quoted 'order-of-magnitude' uncertainty on Κd. We find no evidence that the value of Κd differs significantly between galaxies, or that it correlates with any other measured or derived galaxy properties. We note, however, that the availability of data limits our sample to relatively massive (109.7 < M* < 1011.0M), high metallicity (8.61 < 8.86) galaxies; future work will allow us to investigate a wider range of systems.