How to Correct for Dust Absorption in Starbursts

Abstract

We review new and published results to examine how well the bolometric flux of starbursts can be recovered from ultraviolet (UV) and optical observations. We show that the effective absorption of starbursts can be substantial, up to \~10 mag in the far UV, and ~5 mag in H-alpha, but apparently not as high as some claims in the literature (several tens to a thousand mag). The bolometric fluxes of an IUE sample of starbursts can be recovered to 0.14 dex accuracy using the UV flux and spectral slope. However, this relationship breaks down for Ultra Luminous Infrared Galaxies (ULIGs). The H-alpha flux combined with the Balmer decrement can be used to predict the bolometric flux to 0.5 dex accuracy for starbursts including most ULIGs. These results imply a foreground screen component to the dust distribution.

6 pages, 4 figures; to be published in "Starburst Galaxies Near and Far", eds. D. Lutz and L. Tacconi, Springer