Properties of Submillimeter Galaxies in a Semi-analytic Model using the "Count Matching" Approach: Application to the ECDF-S

Abstract

We present a new technique for modeling submillimeter galaxies (SMGs): the "Count Matching" approach. Using lightcones drawn from a semi-analytic model of galaxy formation, we choose physical galaxy properties given by the model as proxies for their submillimeter luminosities, assuming a monotonic relationship. As recent interferometric observations of the Extended Chandra Deep Field South show that the brightest sources detected by single-dish telescopes are comprised by emission from multiple fainter sources, we assign the submillimeter fluxes so that the combined LABOCA plus bright-end ALMA observed number counts for this field are reproduced. After turning the model catalogs given by the proxies into submillimeter maps, we perform a source extraction to include the effects of the observational process on the recovered counts and galaxy properties. We find that for all proxies, there are lines of sight giving counts consistent with those derived from LABOCA observations, even for input sources with randomized positions in the simulated map. Comparing the recovered redshift, stellar mass and host halo mass distributions for model SMGs with observational data, we find that the best among the proposed proxies is that in which the submillimeter luminosity increases monotonically with the product between dust mass and SFR. This proxy naturally reproduces a positive trend between SFR and bolometric IR luminosity. The majority of components of blended sources are spatially unassociated.

21 pages, 20 figures, 5 tables. Accepted for publication in MNRAS

References in corpus (14)

• Cold streams in early massive hot haloes as the main mode of galaxy formation
• The Mass-Metallicity Relation at z~2
• On the mass-to-light ratio of the local Galactic disc and the optical luminosity of the Galaxy
• The Large APEX Bolometer Camera LABOCA
• Sunrise: Polychromatic Dust Radiative Transfer in Arbitrary Geometries
• An ALMA survey of submillimetre galaxies in the Extended Chandra Deep Field South: High resolution 870um source counts
• AzTEC Millimetre Survey of the COSMOS Field: I. Data Reduction and Source Catalogue
• Submillimetre galaxies in a hierarchical universe: number counts, redshift distribution, and implications for the IMF
• Effects of AGN feedback on LCDM galaxies
• Metal Enrichment of the ICM: a 3-D Picture of Chemical and Dynamical Properties
• Simulated observations of sub-millimetre galaxies: the impact of single-dish resolution and field variance
• Ram pressure stripping in a galaxy formation model. I. A novel numerical approach
• Reproducing the assembly of massive galaxies within the hierarchical cosmogony
• Testing the predictions of the cold dark matter model for the sizes, colours, morphologies and luminosities of galaxies with the SDSS

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• Stellar Populations in a semi-analytic model I: bulges of Milky Way-like galaxies