Title: "Getting Dusty with Bayesian Approaches to the SEDs of High-Redshift Galaxies"
Abstract:
Dust attenuation affects nearly all aspects of galaxy evolution, yet very little is known about the functional form of the dust-attenuation law in the distant Universe.  Dust enshrouds  and obscures star formation, complicating our understanding of galaxy evolution at high redshift.  In this talk, I will summarize recent attempts to quantitatively constrain the wavelength dependence of dust attenuation in high-redshift (z<2) star-forming galaxies. In particular, our Bayesian SED-fitting approach is tested on galaxies at z~2 where CANDELS rest-frame ultra-violet (UV)-to-near-infrared (IR) photometry and Spitzer/Herschel IR luminosities are available.  The dust-attenuation law of individual galaxies, implied from their rest UV-to-near-IR data, agrees with the dust law expected from their IR luminosity and UV color.  Furthermore, a parameterization of the attenuation curve reveals that galaxies with large dust optical depth have a shallower, starburst-like attenuation, and those with small dust optical depth have a steeper, SMC-like attenuation across UV-to-optical wavelengths. Both ends of the relation can be explained by the geometry of dust; the former scenario suggests galaxies have a more mixed star-dust distribution at high dust optical depths, and the latter suggests an attenuation driven by dust scattering at low dust optical depths.