CoMaLit - II. The scaling relation between mass and Sunyaev-Zel'dovich signal for Planck selected galaxy clusters

Abstract

We discuss the scaling relation between mass and integrated Compton parameter of a sample of galaxy clusters from the all-sky Planck Sunyaev-Zel'dovich catalogue. Masses were measured with either weak lensing, caustics techniques, or assuming hydrostatic equilibrium. The retrieved Y<SUB>500</SUB>-M<SUB>500</SUB> relation does not strongly depend on the calibration sample. We found a slope of 1.4-1.9, in agreement with self-similar predictions, with an intrinsic scatter of 20 ± 10 per cent. The absolute calibration of the relation cannot be ascertained due to systematic differences of ̃20-40 per cent in mass estimates reported by distinct groups. Due to the scatter, the slope of the conditional scaling relation, to be used in cosmological studies of number counts, is shallower, ̃1.1-1.6. The regression methods employed account for intrinsic scatter in the mass measurements too. We found that Planck mass estimates suffer from a mass-dependent bias.