Partial Ly$\alpha$ thermalization in an analytic nonlinear diffusion model

Georg Wolschin

doi:10.1038/s41598-024-54833-z

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arXiv · 2402.11320

Partial Ly$\alpha$ thermalization in an analytic nonlinear diffusion model

Georg Wolschin

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Abstract

During recombination, the cosmic background radiation is disturbed, in particular, by Lyman-alpha emissions from neutral hydrogen. It is proposed to account for the subsequent time-dependent partial thermalization of the Lyman-alpha energy content in an analytically solvable nonlinear diffusion model. The amplitude of the partially thermalized and redshifted Ly-$\alpha$ line is found to be too low to be visible in the cosmic microwave spectrum, in accordance with previous numerical models and Planck observations.

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Georg Wolschin. 2024-02-17. Partial Ly$\alpha$ thermalization in an analytic nonlinear diffusion model. https://doi.org/10.1038/s41598-024-54833-z

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