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Cross-Correlation of the Cosmic Microwave Background with Radio Sources: Constraints on an Accelerating Universe

S. P. Boughn·R. G. Crittenden
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Abstract

We present a new limit on the cosmological constant based on the absence of correlations between the cosmic microwave background (CMB) and the distribution of distant radio sources. In the cosmological constant-cold dark matter models currently favored, such correlations should have been produced via the integrated Sachs-Wolfe effect, assuming that radio sources trace the local (z=1) matter density. We find no evidence of correlations between the COBE 53Hz microwave map and the NVSS 1.4 GHz radio survey. The implied 95% CL limit on the cosmological constant is Lambda < 0.74, in marginal agreement with the values suggested by recent measurements of the CMB anisotropy and type-IA supernovae observations, 0.6 < Lambda < 0.7. If the cosmological model does lie in this range, then the integrated Sachs-Wolfe effect should be detectable with upcoming CMB maps and radio surveys.

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S. P. Boughn, R. G. Crittenden. 2001-11-14. Cross-Correlation of the Cosmic Microwave Background with Radio Sources: Constraints on an Accelerating Universe. https://doi.org/10.1103/physrevlett.88.021302

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