2020/03/10 by Eric David Kramer, Eric Kuflik, Noam Levi +2
Physics and Astronomy · #Astrophysics #Cosmology #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Dark energy #Dark fluid #Dark matter #Particle physics #Particle physics theoretical and experimental studies #Physics #Standard Model (mathematical formulation) #Unitarity #hep-ph
paper · pdf · doi:10.1103/physrevlett.126.081802
published as Phys. Rev. Lett. 126, 081802 (2021) · 5 + 1 pages, 3 figures
arxiv created 2020/03/10 · openalex publication_date 2021/02/22 · arxiv updated 2021/03/03 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
We propose a new thermal freeze-out mechanism that results in dark matter masses exceeding the unitarity bound by many orders of magnitude, without violating perturbative unitarity or modifying the standard cosmology. The process determining the relic abundance is \ensuremathχ\ensuremathζ^\ifmmode†\else\textdagger\fi\ensuremath→\ensuremathζ\ensuremathζ, where \ensuremathχ is the dark matter candidate. For m_\ensuremathζ<m_\ensuremathχ<3m_\ensuremathζ, \ensuremathχ is cosmologically long-lived and scatters against the exponentially more abundant \ensuremathζ. Therefore, such a process allows for exponentially heavier dark matter for the same interaction strength as a particle undergoing ordinary 2\ensuremath→2 freeze-out, or equivalently, exponentially weaker interactions for the same mass. We demonstrate this mechanism in a leptophilic dark matter model, which allows for dark matter masses up to 109 GeV.