Star Formation in Herschel's Monsters versus Semi-Analytic Models

C. Gruppioni; F. Calura; F. Pozzi; I. Delvecchio; S. Berta; G. De Lucia; F. Fontanot; A. Franceschini; L. Marchetti; N. Menci; P. Monaco; M. Vaccari

arXiv · 1506.01518

Star Formation in Herschel's Monsters versus Semi-Analytic Models

C. Gruppioni·F. Calura·F. Pozzi·I. Delvecchio·S. Berta·G. De Lucia·F. Fontanot·A. Franceschini·L. Marchetti·N. Menci·P. Monaco·M. Vaccari

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Abstract

We present a direct comparison between the observed star formation rate functions (SFRF) and the state-of-the-art predictions of semi-analytic models (SAM) of galaxy formation and evolution. We use the PACS Evolutionary Probe Survey (PEP) and Herschel Multi-tiered Extragalactic Survey (HerMES) data-sets in the COSMOS and GOODS-South fields, combined with broad-band photometry from UV to sub-mm, to obtain total (IR+UV) instantaneous star formation rates (SFRs) for individual Herschel galaxies up to z~4, subtracted of possible active galactic nucleus (AGN) contamination. The comparison with model predictions shows that SAMs broadly reproduce the observed SFRFs up to z~2, when the observational errors on the SFR are taken into account. However, all the models seem to under-predict the bright-end of the SFRF at z>2. The cause of this underprediction could lie in an improper modelling of several model ingredients, like too strong (AGN or stellar) feedback in the brighter objects or too low fall-back of gas, caused by weak feedback and outflows at earlier epochs.

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C. Gruppioni, F. Calura, F. Pozzi, I. Delvecchio, S. Berta, G. De Lucia, F. Fontanot, A. Franceschini, L. Marchetti, N. Menci, P. Monaco, M. Vaccari. 2015-06-04. Star Formation in Herschel's Monsters versus Semi-Analytic Models. https://arxiv.org/abs/1506.01518

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