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Future Cosmic Microwave Background Constraints to the Baryon Density

Marc Kamionkowski·Gerard Jungman·Arthur Kosowsky·David N. Spergel
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Abstract

We discuss what can be learned about the baryon density from an all-sky map of the cosmic microwave background (CMB) with sub-degree angular resolution. With only minimal assumptions about the primordial spectrum of density perturbations and the values of other cosmological parameters, such a CMB map should be able to distinguish between a Universe with a baryon density near 0.1 and a baryon-dominated Universe. With additional reasonable assumptions, it is conceivable that such measurements will constrain the baryon density to an accuracy similar to that obtained from BBN calculations.

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Marc Kamionkowski, Gerard Jungman, Arthur Kosowsky, David N. Spergel. 1996-01-08. Future Cosmic Microwave Background Constraints to the Baryon Density. https://arxiv.org/abs/astro-ph/9601027

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