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arXiv · 1205.6324

LiHe$^+$ in the early Universe: a full assessment of its reaction network and final abundances

Stefano Bovino·Roman Curik·Daniele Galli·Mario Tacconi·Francesco A. Gianturco
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Abstract

We present the results of quantum calculations based on entirely ab initio methods for a variety of molecular processes and chemical reactions involving the LiHe$^+$ ionic polar molecule. With the aid of these calculations we derive accurate reaction rates and fitting expressions valid over a range of gas temperatures representative of the typical conditions of the pregalactic gas. With the help of a full chemical network, we then compute the evolution of the abundance of LiHe$^+$ as function of redshift in the early Universe. Finally, we compare the relative abundance of LiHe$^+$ with that of other polar cations formed in the same redshift interval.

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Stefano Bovino, Roman Curik, Daniele Galli, Mario Tacconi, Francesco A. Gianturco. 2012-05-29. LiHe$^+$ in the early Universe: a full assessment of its reaction network and final abundances. https://doi.org/10.1088/0004-637x/752/1/19

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