The Evolution of Interstellar Dust Out to z=0.001

Geoffrey C. Clayton

Louisiana State University

Abstract

The recent discovery that the UV dust extinction in starburst galaxies is similar to that found in the Small Magellanic Cloud has motivated a re-investigation of dust extinction found in Local Group galaxies where we can study the dust environment in detail. In particular, while efforts have been made to study interstellar dust in various environments at wavelengths from the x-ray to the radio, a single line of sight is rarely subjected to observations over a wide wavelength range. So, to a large extent studies of interstellar dust in the UV and IR have been two "separate worlds." The result has been models of dust grains which are strongly biased toward fitting observations in one wavelength regime or the other. The absence of sightlines for which both UV and IR data are available makes it difficult to reconcile the constraints derived separately from each wavelength regime. I will present the results of searches for a UV signature of the IR PAH features and for IR absorption features along sightlines which have UV extinction curves.