Large-scale Sunyaev-Zeldovich effect: Measuring statistical properties with multifrequency maps

We study the prospects for extracting detailed statistical properties of th e Sunyaev-Zeldovich (SZ) effect associated with large-scale structure using upcoming multifrequency cosmic microwave background (CMB) experiments. The greatest obstacle to detecting the large-angle signal is the confusion noi se provided by the primary anisotropies themselves, and to a lesser degree Galactic and extragalactic foregrounds. We employ multifrequency subtractio n techniques and the latest foregrounds models to determine the detection t hreshold for the Boomerang, Microwave Anisotropy Probe (MAP; several mu K), and Planck CMB (sub-mu K) experiments. Calibrating a simplified biased-tra cer model of the gas pressure from recent hydrodynamic simulations, we esti mate the SZ power spectrum, skewness, and bispectrum through analytic scali ngs and N-body simulations of the dark matter. We show that the Planck sate llite should be able to measure the SZ effect with sufficient precision to determine its power spectrum and higher order correlations, e.g., the skewn ess and bispectrum. Planck should also be able to detect the cross-correlat ion between the SZ and gravitational lensing effect in the CMB. Detection o f these effects will help determine the properties of the as yet undetected gas, including the manner in which the gas pressure traces the dark matter .