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arXiv · 1901.03726

Impact of Neutrino Properties and Dark Matter on the Primordial Lithium Production

Tahani R. Makki·Mounib F. El Eid·Grant J. Mathews
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Abstract

The light elements up to 7Li were produced by the Standard Big Bang nucleosynthesis (SBBN) in the early universe assuming standard conditions. All observed primordial abundances of these light elements match very well the predicted ones by this SBBN except for 7Li which seems to be overproduced. It is rather challenging to resolve this discrepancy owing to the diverse possibilities affecting the abundance of lithium. In the present work we focus on non-standard possible solutions such as variation of chemical potential and the neutrino temperatures. In addition, the effect of dark matter is also analysed. We find that including these non-standard assumptions helps to reduce the abundance of lithium as predicted by SBBN. We suggest that this could be a possible step toward resolving the lithium problem.

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Tahani R. Makki, Mounib F. El Eid, Grant J. Mathews. 2019-01-11. Impact of Neutrino Properties and Dark Matter on the Primordial Lithium Production. https://doi.org/10.1142/s0218301319500654

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