The Mass-Concentration Relation and the Stellar-to-Halo Mass Ratio in the CFHT Stripe 82 Survey

TL;DR

This paper measures the mass-concentration relation and stellar-to-halo mass ratio using weak lensing data from CFHT Stripe 82, providing results consistent with simulations and previous studies.

Contribution

It offers new measurements of the mass-concentration relation and stellar-to-halo mass ratio over a wide halo mass range using combined weak lensing data and galaxy catalogs.

Findings

Mass-concentration relation parameters are consistent with simulations.

Stellar-to-halo mass ratios align with previous measurements.

Results cover halo masses from 5×10^{12} to 2×10^{14} solar masses.

Abstract

We present a new measurement of the mass-concentration relation and the stellar-to-halo mass ratio over the halo mass range $5\times 10^{12}$ to $2\times 10^{14}M_{\odot}$. To achieve this, we use weak lensing measurements from the CFHT Stripe 82 Survey (CS82), combined with the central galaxies from the redMaPPer cluster catalogue and the LOWZ/CMASS galaxy sample of the Sloan Digital Sky Survey-III Baryon Oscillation Spectroscopic Survey Tenth Data Release. The stacked lensing signals around these samples are modelled as a sum of contributions from the central galaxy, its dark matter halo, and the neighboring halos, as well as a term for possible centering errors. We measure the mass-concentration relation: $c_{200c}(M)=A(\frac{M_{200c}}{M_0})^{B}$ with $A=5.24\pm1.24, B=-0.13\pm0.10$ for $0.2<z<0.4$ and $A=6.61\pm0.75, B=-0.15\pm0.05$ for $0.4<z<0.6$. These amplitudes and slopes are completely consistent with predictions from recent simulations. We also measure the stellar-to-halo mass ratio for our samples, and find results consistent with previous measurements from lensing and other techniques.