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arXiv · 1801.01499

A Model Connecting Galaxy Masses, Star Formation Rates, and Dust Temperatures Across Cosmic Time

Nia Imara·Abraham Loeb·Benjamin D. Johnson·Charlie Conroy·Peter Behroozi
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Abstract

We investigate the evolution of dust content in galaxies from redshifts z=0 to z=9.5. Using empirically motivated prescriptions, we model galactic-scale properties -- including halo mass, stellar mass, star formation rate, gas mass, and metallicity -- to make predictions for the galactic evolution of dust mass and dust temperature in main sequence galaxies. Our simple analytic model, which predicts that galaxies in the early Universe had greater quantities of dust than their low-redshift counterparts, does a good job at reproducing observed trends between galaxy dust and stellar mass out to z~6. We find that for fixed galaxy stellar mass, the dust temperature increases from z=0 to z=6. Our model forecasts a population of low-mass, high-redshift galaxies with interstellar dust as hot as, or hotter than, their more massive counterparts; but this prediction needs to be constrained by observations. Finally, we make predictions for observing 1.1-mm flux density arising from interstellar dust emission with the Atacama Large Millimeter Array.

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Nia Imara, Abraham Loeb, Benjamin D. Johnson, Charlie Conroy, Peter Behroozi. 2018-01-04. A Model Connecting Galaxy Masses, Star Formation Rates, and Dust Temperatures Across Cosmic Time. https://doi.org/10.3847/1538-4357/aaa3f0

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