Interpreting the Cosmic Infrared Background: Constraints on the Evolution of the Dust‐enshrouded Star Formation Rate

Dusty star-forming galaxies at high redshift

“…In contrast to the Silva et al (1998) and Chary & Elbaz (2001) work, Dale et al (2001) present a different model for SEDs in the far-infrared. SEDs are constructed from various dust emission curves and the assumption that there is a power-law distributions of dust masses (thus dust temperatures) over a wide range of radiation fields.…”

“…The Chary & Elbaz (2001) and Dale & Helou (2002) have garnered significant traction in the dusty galaxy community for SED fitting, particularly for galaxies detected in the mid-IR for which estimates of far-IR emission are necessary, but newer models have recently become available which make use of more sophisticated, later datasets and modeling techniques specifically tweaked for extreme starbursts. Siebenmorgen & Krügel (2007) describe a spherically symmetric radiative transfer model for dusty starburst nuclei and ULIRGs and argue that the symmetry assumption, and lack of accounting for dust clumpiness, does not significantly change a dusty galaxy's SED.…”

“…Despite the relative lack of detailed data, detailed radiative transfer models and empirical template libraries have modeled the complex dust infrared emission from stars, molecular clouds and dust grains over a wide range of galaxy geometries and luminosities (Silva et al, 1998;Chary & Elbaz, 2001;Dale et al, 2001;Dale & Helou, 2002;Abel & Wandelt, 2002;Siebenmorgen & Krügel, 2007;Draine & Li, 2007). When discussing these models, it's important to keep in mind that the accuracy or applicability of these models cannot be tested with data since it simply does not exist in enough detail to disentangle effects of geometry, distribution, optical depth, etc.…”

“…They use stellar population synthesis models and a chemical evolution code to generate integrated spectra for simple stellar populations of different ages, metallicities, star formation rates, gas fractions, relative gas trapped in molecular clouds versus diffuse ISM, dust geometry and dust grain size distribution (small grains versus PAHs). Chary & Elbaz (2001) use Grasil and the analysis of Silva et al (1998) to generate template SEDs for infrared-luminous galaxies out to moderately high redshifts (z ∼ 1) when measuring contributions of different galaxy populations to the CIB. Chary & Elbaz generate four SEDs with Grasil to fit data from nearby galaxies which each represent a different decade in infrared luminosity−Arp 220, NGC 6090, M 82, and M 51.…”

“…Mid-IR spectral features taken from ISO observations. Chary & Elbaz (2001) 105 templates; used basic Silva et al (1998) models to reproduce SEDs for four local galaxies (Arp 220, NGC 6090, M 82, M 51, representing ULIRGs, LIRGs, starbursts and normal galaxies) and ISOCAM CVF 3-18µm observations to determine mid-IR spectra and continuum strength. Interpolated between four SEDs and used Dale et al (2001) templates to create a larger range of FIR spectral shapes.…”