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arXiv · 1402.1495

A Two-Parameter Model for the Infrared/Submillimeter/Radio Spectral Energy Distributions of Galaxies and AGN

Daniel A. Dale·George Helou·Georgios E. Magdis·Lee Armus·Tanio Díaz-Santos·Yong Shi
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Abstract

A two-parameter semi-empirical model is presented for the spectral energy distributions of galaxies with contributions to their infrared-submillimeter-radio emission from both star formation and accretion disk-powered activity. This model builds upon a previous one-parameter family of models for star-forming galaxies, and includes an update to the mid-infrared emission using an average template obtained from Spitzer Space Telescope observations of normal galaxies. Star-forming/AGN diagnostics based on PAH equivalent widths and broadband infrared colors are presented, and example mid-infrared AGN fractional contributions are estimated from model fits to the GOALS sample of nearby U/LIRGS and the 5MUSES sample of 24um-selected sources at redshifts 0 < z < 2.

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Daniel A. Dale, George Helou, Georgios E. Magdis, Lee Armus, Tanio Díaz-Santos, Yong Shi. 2014-02-06. A Two-Parameter Model for the Infrared/Submillimeter/Radio Spectral Energy Distributions of Galaxies and AGN. https://doi.org/10.1088/0004-637x%2F784%2F1%2F83

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