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arXiv · 1511.00672

Bounds on very low reheating scenarios after Planck

P. F. de Salas·M. Lattanzi·G. Mangano·G. Miele·S. Pastor·O. Pisanti
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Abstract

We consider the case of very low reheating scenarios ($T_{\rm RH}\sim\mathcal{O}({\rm MeV})$) with a better calculation of the production of the relic neutrino background (with three-flavor oscillations). At 95% confidence level, a lower bound on the reheating temperature $T_{\rm RH}>4.1$ MeV is obtained from Big Bang Nucleosynthesis, while $T_{\rm RH}>4.3$ MeV from Planck data for very light ($\sum m_i = 0.06$ eV) neutrinos. If neutrino masses are allowed to vary, Planck data yield $T_{\rm RH}>4.7$ MeV, the most stringent bound on the reheating temperature to date. Neutrino masses as large as 1 eV are possible for very low reheating temperatures.

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P. F. de Salas, M. Lattanzi, G. Mangano, G. Miele, S. Pastor, O. Pisanti. 2015-11-02. Bounds on very low reheating scenarios after Planck. https://doi.org/10.1103/physrevd.92.123534

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