We present a statistical weak-lensing magnification analysis on an optically selected sample of 3029 CAMIRA galaxy clusters with richness N > 15 in the Subaru Hyper Suprime-Cam ( HSC ) survey .
The CAMIRA sample spans a wide redshift range of 0.2 \leq z < 1.1 .
We use two distinct populations of color-selected , flux-limited background galaxies , namely the low- z and high- z samples at mean redshifts of \approx 1.1 and \approx 1.4 , respectively , from which to measure the weak-lensing magnification signal by accounting for cluster contamination as well as masking effects .
Our magnification bias measurements are found to be uncontaminated according to validation tests against the ‘ ‘ null-test ’ ’ samples for which the net magnification bias is expected to vanish .
The magnification bias for the full CAMIRA sample is detected at a significance level of 8.29 \sigma , which is dominated by the high- z background .
We forward-model the observed magnification data to constrain the richness-to-mass ( N – M ) relation for the CAMIRA sample .
In this work , we can only constrain the normalization of the N – M relation by employing informative priors on the mass and redshift trends , and on the intrinsic scatter at fixed mass .
The resulting scaling relation is N \propto { M _ { 500 } } ^ { 0.91 \pm 0.14 } ( 1 + z ) ^ { -0.45 \pm 0.75 } , with a characteristic richness of N = \left ( 19.63 \pm 3.16 \right ) and intrinsic log-normal scatter of 0.14 \pm 0.07 at M _ { 500 } = 10 ^ { 14 } h ^ { -1 } \mathrm { M } _ { \odot } .
With the derived N – M relation , we provide magnification-calibrated mass estimates of individual CAMIRA clusters , with the typical uncertainty of \approx 38 \% and \approx 30 \% at richness \approx 20 and \approx 40 , respectively .
We further compare our magnification-inferred N – M relation with those from the shear-based results in the literature , finding good agreement .