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arXiv · 1809.10416

Comparison of cosmological simulations and deep submillimetre galaxy surveys

Shohei Aoyama·Hiroyuki Hirashita·Chen-Fatt Lim·Yu-Yen Chang·Wei-Hao Wang·Kentaro Nagamine·Kuan-Chou Hou·Ikkoh Shimizu·Hui-Hsuan Chung·Chien-Hsiu Lee·Xian-Zhong Zheng
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Abstract

Recent progress in submillimetre surveys by single-dish telescopes allows us to further challenge the consistency between cosmological simulations and observations. In particular, we compare our simulations that include dust formation and destruction with the recent SCUBA-2 surveys (`STUDIES') by putting emphases on basic observational properties of dust emission such as dust temperature, size of infrared (IR)-emitting region, IR luminosity function and IRX--$β$ relation. After confirming that our models reproduce the local galaxy properties, we examine the STUDIES sample at $z\approx 1-4$, finding that the simulation reproduces the aforementioned quantities except for the $z\gtrsim 2$ IR luminosity function at the massive end ($\sim 10^{13}$ L$_{\odot}$). This means that the current simulation correctly reproduces the overall scaling between the size and luminosity (or star formation rate) of dusty region, but lacks extreme starburst phenomena at $z\gtrsim 2$. We also discuss extinction curves and possible AGN contribution.

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Shohei Aoyama, Hiroyuki Hirashita, Chen-Fatt Lim, Yu-Yen Chang, Wei-Hao Wang, Kentaro Nagamine, Kuan-Chou Hou, Ikkoh Shimizu, Hui-Hsuan Chung, Chien-Hsiu Lee, Xian-Zhong Zheng. 2019-01-21. Comparison of cosmological simulations and deep submillimetre galaxy surveys. https://doi.org/10.1093/mnras%2Fstz021

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