Cross-correlating the Microwave Sky with Galaxy Surveys

Pablo Fosalba (1, 2) , Enrique Gaztanaga (3, 4) , Francisco J. Castander (3)

1 Institute for Astronomy [Honolulu]
2 IAP - Institut d'Astrophysique de Paris
3 ICE-CSIC - Institut de Ciencies de l'Espai [Barcelona]
4 INAOE - Instituto Nacional de Astrofísica, Óptica y Electrónica

We present results for the cross-correlation between the WMAP 1st-year cosmic microwave background (CMB) anisotropy data and optical galaxy surveys: the APM and SDSS DR1 catalogs. Our measurement of a positive CMB-galaxy correlation on large angles (\theta > 4 deg)yields significant detections of theIntegrated Sachs-Wolfe (ISW) effect and provides a new estimate of dark-energy in the universe, \Omega_\Lambda=0.69-0.86 (2 \sigma range). In addition, the correlated signal on small angles (\theta<1 deg) reveals the imprint left by hot intra-cluster gas in the CMB photons:the thermal Sunyaev-Zeldovich (SZ) effect

Domaines: Cosmologie et astrophysique extra-galactique [astro-ph.CO]

Pablo Fosalba, Enrique Gaztanaga, Francisco J. Castander. Cross-correlating the Microwave Sky with Galaxy Surveys. 2003. ⟨hal-00000741v3⟩