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New Constraint on Open Cold-Dark-Matter Models

Ali Kinkhabwala·Marc Kamionkowski
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Abstract

We calculate the large-angle cross-correlation between the cosmic-microwave-background (CMB) temperature and the x-ray-background (XRB) intensity expected in an open Universe with cold dark matter (CDM) and a nearly scale-invariant spectrum of adiabatic density perturbations. Results are presented as a function of the nonrelativistic-matter density $Ω_0$ (in units of the critical density) and the x-ray bias $b_x$ (evaluated at a redshift $z\simeq1$ in evolving-bias models) for both an open Universe and a flat cosmological-constant Universe. Recent experimental upper limits to the amplitude of this cross-correlation provide a new constraint to the $Ω_0$-$b_x$ parameter space that open-CDM models (and the open-inflation models that produce them) must satisfy.

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Ali Kinkhabwala, Marc Kamionkowski. 1999-05-03. New Constraint on Open Cold-Dark-Matter Models. https://doi.org/10.1103/physrevlett.82.4172

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