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arXiv · 1710.06872

The Constant Average Relationship between Dust-obscured Star Formation and Stellar Mass from $z=0$ to $z=2.5$

Katherine E. Whitaker·Alexandra Pope·Ryan Cybulski·Caitlin M. Casey·Gergö Popping·Min S. Yun
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Abstract

The total star formation budget of galaxies consists of the sum of the unobscured star formation, as observed in the rest-frame ultraviolet (UV), together with the obscured component that is absorbed and re-radiated by dust grains in the infrared. We explore how the fraction of obscured star formation depends on stellar mass for mass-complete samples of galaxies at $0 1$. For log(M/M$_{\odot}$)$>$10.5, $>$90\% of star formation is obscured at all redshifts. We also show that at fixed total SFR, $f_{\mathrm{obscured}}$ is lower at higher redshift. At fixed mass, high-redshift galaxies are observed to have more compact sizes and much higher star formation rates, gas fractions and hence surface densities (implying higher dust obscuration), yet we observe no redshift evolution in $f_{\mathrm{obscured}}$ with stellar mass. This poses a challenge to theoretical models to reproduce, where the observed compact sizes at high redshift seem in tension with lower dust obscuration.

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Katherine E. Whitaker, Alexandra Pope, Ryan Cybulski, Caitlin M. Casey, Gergö Popping, Min S. Yun. 2017-10-18. The Constant Average Relationship between Dust-obscured Star Formation and Stellar Mass from $z=0$ to $z=2.5$. https://doi.org/10.3847/1538-4357%2Faa94ce

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