Detection of the integrated Sachs-Wolfe and Sunyaev-Zeldovich effects from the cosmic microwave background-galaxy correlation

作者：Fosalba P^*; Gaztanaga E; Castander FJ

来源：Astrophysical Journal, 2003, 597(2): L89-L92.

DOI：10.1086/379848

• cosmic microwave background
• cosmology : observations

We present a cross-correlation analysis of the Wilkinson 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 (zsimilar to0.3) and a high-redshift (zsimilar to0.5) color-selected sample. The signal is compatible with that expected from the integrated Sachs-Wolfe (ISW) effect at large angles (theta>4degrees) and the Sunyaev-Zeldovich (SZ) effect at small scales (theta<1&DEG;). The detected correlation at low z is in good agreement with a previous analysis using the Automated Plate Measuring survey (z&SIM;0.15). The combined analysis of all three samples yields a total significance of better z&SIM;0.15 than 3 σ for the ISW effect and of about 2.7 σ for the SZ effect, with a Compton parameter <(y)over bar>similar or equal to10(-6). For a given flat Lambda cold dark matter model, the ISW effect depends on both the value of Omega(Lambda) 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: Omega(Lambda)similar or equal to0.8, with a 2 sigma error Omega(Lambda)=0.69-0.86.

• 出版日期2003-11-10