Weak lensing as a calibrator of the cluster mass-temperature relation

The abundance of clusters at the present epoch and weak gravitational lensing shear both constrain roughly the same combination of the power spectrum normalization sigma(s) and matter energy density Omega(M). The cluster constraint further depends on the normalization of the mass-temperature relation. Therefore, combining the weak-lensing and cluster abundance data can be used to accurately calibrate the mass-temperature relation. We discuss this approach and illustrate it using data from recent surveys.