The Cluster SZ -- Mass Correlation
  N-body + hydrodynamic simulations of galaxy clusters are used to demonstrate a correlation between galaxy cluster mass and the strength of the Sunyaev-Zel'dovich (SZ) effect induced by the cluster. The intrinsic scatter in the correlaton is larger than seen in the cluster mass -- X-ray temperature correlation, but smaller than seen in the correlation between mass (or temperature) and X-ray luminosity, as expected. Using the convergence to self-similarity of cluster structure at larger radii, a simple area-averaged SZ value derived from mock SZ maps also correlates well with mass; the intrinsic scatter in this correlation is comparable to that seen in simulations for the mass -- temperature correlation. Such a relation may prove a powerful tool for estimating cluster masses at higher redshifts. 
Christopher A. Metzler (University of Illinois and NASA/Fermilab   Astrophysics Center)