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