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arXiv · 1610.09383

Weak lensing measurement of the mass-richness relation using the SDSS database

Elizabeth Johana Gonzalez·Facundo Rodriguez·Diego García Lambas·Manuel Merchán·Gael Foëx·Martín Chalela
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Abstract

We study the mass-richness relation using galaxy catalogues and images from the Sloan Digital Sky Survey. We use two independent methods, in the first one, we calibrate the scaling relation with weak-lensing mass estimates. In the second procedure we apply a background subtraction technique to derive the probability distribution, $P(M \mid N)$, that groups with $N$-members have a virialized halo mass $M$. Lensing masses are derived in different richness bins for two galaxy systems sets: the maxBCG catalogue and a catalogue based on a group finder algorithm developed by Yang et al. MaxBCG results are used to test the lensing methodology. The lensing mass-richness relation for the Yang et al. group sample shows a good agreement with $P(M \mid N)$ obtained independently with a straightforward procedure.

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Elizabeth Johana Gonzalez, Facundo Rodriguez, Diego García Lambas, Manuel Merchán, Gael Foëx, Martín Chalela. 2017-02-01. Weak lensing measurement of the mass-richness relation using the SDSS database. https://doi.org/10.1093/mnras%2Fstw2803

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