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arXiv · 2412.01470

Asymmetric dark matter from semi-annihilation: unitarity constraints and long-lived final states

Tomáš Blažek·Peter Maták·Viktor Zaujec
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Abstract

This work presents an asymmetric dark matter model with relic density determined by the freeze-out of asymmetric semi-annihilations into long-lived particles slowly decaying into the Standard Model states. We carefully consider the $CPT$ symmetry and unitarity constraints to the asymmetries entering the Boltzmann equation. The main idea of the paper is to point out a critical inconsistency in the previous literature, where these constraints are violated. We present a systematic approach to avoid the inconsistency.

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Tomáš Blažek, Peter Maták, Viktor Zaujec. 2024-12-02. Asymmetric dark matter from semi-annihilation: unitarity constraints and long-lived final states. https://doi.org/10.1007/jhep04(2025)104

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