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arXiv · 1905.05170

Dark matter component decaying after recombination: constraints from diffuse gamma-ray and neutrino flux measurements

Oleg E. Kalashev·Mikhail Yu. Kuznetsov·Yana V. Zhezher
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Abstract

We consider scenario of the dark matter consisting of two fractions, stable part being dominant and a smaller unstable fraction, which has decayed after the recombination epoch. It has been suggested in Ref. [arxiv:1505.03644] that the above scenario may alleviate tension between high-redshift (CMB anisotropy) and low-redshift (cepheid variables and SNe Ia, cluster counts) cosmological measurements. We derive constraints on the heavy relics branching to $q\bar{q}$, $e^+e^-$, $\mu^+\mu^-$, $\tau^+\tau^-$, $\nu_e\bar{\nu_e}$, $\nu_\mu\bar{\nu_\mu}$, $W^+W^-$ and $\gamma\gamma$ in the above scenario by comparison of the secondary $\gamma$ and $\nu$ fluxes produced by the process with recent diffuse $\gamma$ and $\nu$ flux measurements.

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Oleg E. Kalashev, Mikhail Yu. Kuznetsov, Yana V. Zhezher. 2019-05-13. Dark matter component decaying after recombination: constraints from diffuse gamma-ray and neutrino flux measurements. https://doi.org/10.1088/1475-7516%2F2019%2F10%2F039

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