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Recombination Induced Softening and Reheating of the Cosmic Plasma

Po Kin Leung·Chi-Wang Chan·Ming-Chung Chu
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Abstract

The atomic recombination process leads to a softening of the matter equation of state as reflected by a reduced generalized adiabatic index, with accompanying heat release. We study the effects of this recombination softening and reheating of the cosmic plasma on the ionization history, visibility function, Cold Dark Matter (CDM) transfer function, and the Cosmic Microwave Background (CMB) spectra. The resulting modifications of the CMB spectrm is 1/10 of WMAP's current error and is comparable to PLANCK's error. Therefore, this effect should be considered when data with higher accuracy are analysed.

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Po Kin Leung, Chi-Wang Chan, Ming-Chung Chu. 2003-12-10. Recombination Induced Softening and Reheating of the Cosmic Plasma. https://doi.org/10.1111/j.1365-2966.2004.07524.x

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