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arXiv · 1811.02518

Luminous red galaxies in the Kilo Degree Survey: selection with broad-band photometry and weak lensing measurements

Mohammadjavad Vakili·Maciej Bilicki·Henk Hoekstra·Nora Elisa Chisari·Christos Georgiou·Arun Kannawadi·Koen Kuijken·Angus H. Wright
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Abstract

We use the overlap between multiband photometry of the Kilo-Degree Survey (KiDS) and spectroscopic data based on the Sloan Digital Sky Survey (SDSS) and Galaxy And Mass Assembly (GAMA) to infer the colour-magnitude relation of red-sequence galaxies. We then use this inferred relation to select luminous red galaxies (LRGs) in the redshift range of $0.1<z<0.7$ over the entire KiDS Data Release 3 footprint. We construct two samples of galaxies with different constant comoving densities and different luminosity thresholds. The selected red galaxies have photometric redshifts with typical photo-z errors of $\sigma_z \sim 0.014 (1+z)$ that are nearly uniform with respect to observational systematics. This makes them an ideal set of galaxies for lensing and clustering studies. As an example, we use the KiDS-450 cosmic shear catalogue to measure the mean tangential shear signal around the selected LRGs. We detect a significant weak lensing signal for lenses out to $z \sim 0.7$.

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Mohammadjavad Vakili, Maciej Bilicki, Henk Hoekstra, Nora Elisa Chisari, Christos Georgiou, Arun Kannawadi, Koen Kuijken, Angus H. Wright. 2018-11-06. Luminous red galaxies in the Kilo Degree Survey: selection with broad-band photometry and weak lensing measurements. https://doi.org/10.1093/mnras/stz1249

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