LoCuSS: A Comparison of Sunyaev-Zel'dovich Effect and Gravitational Lensing Measurements of Galaxy Clusters

We present the first measurement of the relationship between the Sunyaev-Zel'dovich effect (SZE) signal and the mass of galaxy clusters that uses gravitational lensing to measure cluster mass, based on 14 X-ray luminous clusters at z similar or equal to 0.2 from the Local Cluster Substructure Survey. We measure the integrated Compton y-parameter, Y, and total projected mass of the clusters (M-GL) within a projected clustercentric radius of 350 kpc, corresponding to mean overdensities of 4000-8000 relative to the critical density. We find self-similar scaling between M-GL and Y, with a scatter in mass at fixed Y of 32%. This scatter exceeds that predicted from numerical cluster simulations, however, it is smaller than comparable measurements of the scatter in mass at fixed T-X. We also find no evidence of segregation in Y between disturbed and undisturbed clusters, as had been seen with T-X on the same physical scales. We compare our scaling relation to the Bonamente et al. relation based on mass measurements that assume hydrostatic equilibrium, finding no evidence for a hydrostatic mass bias in cluster cores (M-GL = 0.98 +/- 0.13 M-HSE), consistent with both predictions from numerical simulations and lensing/X-ray-based measurements of mass-observable scaling relations at larger radii. Overall our results suggest that the SZE may be less sensitive than X-ray observations to the details of cluster physics in cluster cores.