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arXiv · 2209.04644

Formation of primordial helium: a rapid and simple scheme of calculation

Tamaz Kereselidze·Zaal Machavariani·Irakli Noselidze
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Abstract

A rapid and relatively simple scheme of calculation is elaborated and applied to cosmological recombination of helium. Employing the nonrelativistic Coulomb Green's function, a wavefunction of a colliding electron is represented in an integral form applicable for calculations. Bound electrons of helium are described by the Hartree-Fock wavefunctions. The free-bound transition probabilities into excited states of helium, and the probabilities of bound-bound transitions in helium are calculated in different modes. It is revealed that free-bound transition probabilities weakly depend on to what extent a field experienced by a colliding electron deviates from the purely Coulomb field with charge Z=1, whereas these probabilities strongly depend on the choice of a wavefunction of a bound active electron involved in recombination.

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Tamaz Kereselidze, Zaal Machavariani, Irakli Noselidze. 2022-09-10. Formation of primordial helium: a rapid and simple scheme of calculation. https://arxiv.org/abs/2209.04644

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