Dust in Starburst Galaxies

K. D. Gordon, D. Calzetti, & A. N. Witt 1997, in "The Ultraviolet Universe at Low and High Redshift: Probing the Progress of Galaxy Evolution", AIP Conference Proc. No. 408, eds. W. H. Waller, M. N. Fanelli, J. E. Hollis, & A. C. Danks (New York: AIP Press), 364

To investigate the nature of starbursts' dust, we constructed a model of the stars and dust in starburst galaxies and applied it to 30 observed starburst SEDs. The starburst model was constructed by combining two stellar evolutionary synthesis models with a model describing the radiative transfer of stellar photons through dust. Using color-color plots, the starburst model was used to interpret the behavior of 30 starbursts with aperture-matched UV and optical SEDs (and IR for 19 of the 30) from previous studies. From the UV color-color plots, it was evident that the dust in starbursts has an extinction curve lacking a 2175 A bump, like the SMC curve, and a steep far-UV rise, intermediate between the MW and SMC curves. The star/dust geometry which was able to explain the distribution of the 30 starbursts in various color-color plots was a clumpy shell geometry. When combined with other work from the literature on the Orion region and the 30 Dor region of the Large Magellanic Cloud, this work implies a trend in dust properties with star formation intensity.

[Preprint]