Gravitational lensing magnification is measured with a significance of 9.7 \sigma on a large sample of galaxy clusters in the Canada-France-Hawaii Telescope Lensing Survey ( CFHTLenS ) .
This survey covers \sim 154 deg ^ { 2 } and contains over 18,000 cluster candidates at redshifts 0.2 \leq z \leq 0.9 , detected using the 3D-Matched Filter cluster-finder of .
We fit composite-NFW models to the ensemble , accounting for cluster miscentering , source-lens redshift overlap , as well as nearby structure ( the 2-halo term ) , and recover mass estimates of the cluster dark matter halos in range of \sim 10 ^ { 13 } M _ { \odot } to 2 \times 10 ^ { 14 } M _ { \odot } .
Cluster richness is measured for the entire sample , and we bin the clusters according to both richness and redshift .
A mass-richness relation M _ { 200 } = M _ { 0 } ( N _ { 200 } / 20 ) ^ { \beta } is fit to the measurements .
For two different cluster miscentering models we find consistent results for the normalization and slope , M _ { 0 } = ( 2.3 \pm 0.2 ) \times 10 ^ { 13 } M _ { \odot } , \beta = 1.4 \pm 0.1 and M _ { 0 } = ( 2.2 \pm 0.2 ) \times 10 ^ { 13 } M _ { \odot } , \beta = 1.5 \pm 0.1 .
We find that accounting for the full redshift distribution of lenses and sources is important , since any overlap can have an impact on mass estimates inferred from flux magnification .