Abstract
We describe a nonparametric method to reconstruct gas density and temperature profiles of galaxy clusters from observations of X-ray surface brightness, emission-weighted temperature, and the yparameter through the Sunyaev-Zeldovich effect. This method is based on the inversion of the projected profiles under the spherically symmetric approximation, which is independent of the equation of state of cluster gas and does not assume that the gas is in hydrostatic equilibrium. In particular, we examine the reliability of the reconstruction method assuming a few theoretical models for cluster gas and assigning the statistical errors expected for future X-ray and radio observations. We also discuss briefly the effect of nonsphericity on the basis of simulated clusters.