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We present the cluster mass-richness scaling relation calibrated by a weak lensing analysis of ≿ 18 000 galaxy cluster candidates in the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS). Detected using the 3D-Matched-Filter (MF) cluster-finder of Milkeraitis et al., these cluster candidates span a wide range of masses, from the small group scale up to ~1015M⊙, andredshifts 0.2 ≲ z ≲ <0.9. The total significance of the stacked shear measurement amounts to 54σ. We compare cluster masses determined using weak lensing shear and magnification, finding the measurements in individual richness bins to yield 1σ compatibility, but with magnification estimates biased low. This first direct mass comparison yields important insights for improving the systematics handling of future lensing magnification work. In addition, we confirm analyses that suggest cluster miscentring has an important effect on the observed 3D-MF halo profiles, and we quantify this by fitting for projected cluster centroid offsets, which are typically ~0.4 arcmin. We bin the cluster candidates as a function of redshift, finding similar cluster masses and richness across the full range up to z ~ 0.9. We measure the 3D-MF mass-richness scaling relation M200 = M0 (N200/20)β. We find a normalization M0 ~ (2.7-0.4+0.5) x 1013M⊙, and a logarithmic slope of β ~ 1.4 ± 0.1, both of which are in 1σ agreement with results from the magnification analysis. We find no evidence for a redshift dependence of the normalization. The CFHTLenS 3D-MF cluster catalogue is now available at cfhtlens.org. [ABSTRACT FROM AUTHOR]

We present photometric, spectroscopic and weak lensing analysis of the large-scale structure and dynamics of the most X-ray luminous galaxy cluster known, RX , at . We spectroscopically confirmed 47 new members with Low Dispersion Survey Spectrograph 3 (LDSS3) on the Magellan telescope. Together with previously known members, we measure a new velocity dispersion of . The mass inferred from our velocity dispersion is , with , under the assumption of a singular isothermal sphere. We also present a weak lensing analysis using deep Canada–France–Hawaii Telescope (CFHT) data on this cluster, and find a deprojected mass of within r200, in excellent agreement with our dynamical estimate. Thus, our new dynamical mass estimate is consistent with that from weak lensing and X-ray studies in the literature, resolving a previously claimed discrepancy. We photometrically detect and spectroscopically confirm another massive cluster with and south-west of RX , which we refer to as . Our spectroscopic survey reveals a possible excess of galaxies in velocity space in the region between RX and ; comparing with simulations, this excess appears consistent with that expected from a large filamentary structure traced by galaxies connecting these two clusters. [ABSTRACT FROM AUTHOR]