Anisotropies in the microwave background due to the Sunyaev-Zel'dovich effect from virialized objects at high redshifts

Abstract

We estimate the anisotropy of the cosmic microwave background radiation via the Sunyaev-Zel'dovich effect of clusters of galaxies in cold dark matter (CDM) and Peebles isocurvature baryon (PIB) models for a wide range of cosmological parameters. The predicted amplitudes are compared with the observational upper limit imposed from the triple beam switching experiment at Owens Valley Radio Observatory. The temperature anisotropies predicted in CDM models with the Harrison-Zel'dovich scale-invariant spectrum are below the current observational limit, while PIB models are compatible with the limit only for the n = -1 models with Ω0 ≤ 0.1, λ0 = 1 - Ω0, and h = 0.5, where n is the spectral index of the primordial entropy fluctuations, and Ω0, λ0, and h are the cosmological density parameter, cosmological constant and the Hubble constant in units of 100 km s-1 Mpc-1. The n = 0 PIB models have too much small-scale power leading to the larger Sunyaev-Zel'dovich temperature fluctuations than the n = -1 models.