Probing SZ Source Detection with Gasdynamical Simulations

Abstract

The huge worldwide investment in CMB experiments should make the Sunyaev-Zeldovich (SZ) effect a key probe of the cosmic web in the near future. For the promise to be realized, substantial development of simulation and analysis tools to relate observation to theory is needed. The high nonlinearity and dissipative/feedback gas physics lead to highly non-Gaussian patterns that are much more difficult to analyze than Gaussian primary anisotropies for which the procedures are reasonably well developed. Historical forecasts for what CMB experiments might see used semi-analytic tools, including large scale map constructions, with localized and simplified pressure structures distributed on a point process of (clustered) sources. Hydro studies beyond individual cluster/supercluster systems were inadequate, but now large-volume simulations with high resolution are beginning to shift the balance. We illustrate this by applying ``Gasoline'' (parallelized Tree+SPH) computations to construct SZ maps and derive statistical measures. We believe rapid Monte Carlo simulations using parameterized templates centered on point processes informed by optical and other means on the observational side, and by hydro simulations on the theory side, should play an important role in pipelines to analyze the new SZ field data. We show that localized sources should dominate upcoming SZ experiments, identify sources in the maps under filtering and noise levels expected for these experiments, use the RCS photometric optical survey as an example of redshift localization, and discuss whether cosmic web patterns such as superclusters can be enhanced when such extra source information is supplied.