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arXiv · 2305.07464

The Spitzer Extragalactic Representative Volume Survey and DeepDrill extension: clustering of near-infrared galaxies

Abstract

We have measured the angular auto-correlation function of near-infrared galaxies in SERVS+DeepDrill, the Spitzer Extragalactic Representative Volume Survey and its follow-up survey of the Deep Drilling Fields, in three large fields totalling over 20 sq. deg on the sky, observed in two bands centred on 3.6 and 4.5 micron. We performed this analysis on the full sample as well as on sources selected by [3.6]-[4.5] colour in order to probe clustering for different redshift regimes. We estimated the spatial correlation strength as well, using the redshift distribution from S-COSMOS with the same source selection. The strongest clustering was found for our bluest subsample, with z~0.7, which has the narrowest redshift distribution of all our subsamples. We compare these estimates to previous results from the literature, but also to estimates derived from mock samples, selected in the same way as the observational data, using deep light-cones generated from the SHARK semi-analytical model of galaxy formation. For all simulated (sub)samples we find a slightly steeper slope than for the corresponding observed ones, but the spatial clustering length is comparable in most cases.

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Eelco van Kampen, Mark Lacy, Duncan Farrah, Claudia del P. Lagos, Matt Jarvis, Claudia Maraston, Kristina Nyland, Seb Oliver, Jason Surace, Jessica Thorne. 2023-05-12. The Spitzer Extragalactic Representative Volume Survey and DeepDrill extension: clustering of near-infrared galaxies. https://doi.org/10.1093/mnras%2Fstad1466

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