Detection of the Integrated Sachs-Wolfe and Sunyaev-Zeldovich Effects from the Cosmic Microwave Background-Galaxy Correlation

Abstract

We present a cross-correlation analysis of the W ilkinson Microwave Anisotropy Probe cosmic microwave background (CMB) temperature anisotropies and the Sloan Digital Sky Survey galaxy density fluctuations. We find significant detections of the angular CMB-galaxy correlation for both a flux-limited galaxy sample ( z ~ 0.3) and a high-redshift ( z ~ 0.5) color-selected sample. The signal is compatible with that expected from the integrated Sachs-Wolfe (ISW) effect at large angles (θ > 4°) and the Sunyaev-Zeldovich (SZ) effect at small scales (θ < 1°). The detected correlation at low z is in good agreement with a previous analysis using the Automated Plate Measuring survey ( z ~ 0.15). The combined analysis of all three samples yields a total significance of better than 3 σ for the ISW effect and of about 2.7 σ for the SZ effect, with a Compton parameter ≃ 10 -6 . For a given flat Λ cold dark matter model, the ISW effect depends on both the value of Ω Λ and the galaxy bias b . To break this degeneracy, we estimate the bias using the ratio between the galaxy and mass autocorrelation functions in each sample. With our bias estimation, all samples consistently favor a best-fit dark-energy-dominated model: Ω Λ ≃ 0.8, with a 2 σ error Ω Λ = 0.69-0.86.