Big bang darkleosynthesis
- Publisher: Elsevier BV
Physics Letters B,
(issn: 0370-2693, eissn: 1873-2445)
High Energy Physics - Phenomenology | Physics | QC1-999 | Astrophysics - Cosmology and Nongalactic Astrophysics | Nuclear and High Energy Physics
In a popular class of models, dark matter comprises an asymmetric population of composite particles with short range interactions arising from a confined nonabelian gauge group. We show that coupling this sector to a well-motivated light mediator particle yields efficient darkleosynthesis , a dark-sector version of big-bang nucleosynthesis (BBN), in generic regions of parameter space. Dark matter self-interaction bounds typically require the confinement scale to be above ΛQCD , which generically yields large ( ≫MeV/dark-nucleon ) binding energies. These bounds further suggest the mediator is relatively weakly coupled, so repulsive forces between dark-sector nuclei are much weaker than Coulomb repulsion between standard-model nuclei, which results in an exponential barrier-tunneling enhancement over standard BBN. Thus, darklei are easier to make and harder to break than visible species with comparable mass numbers. This process can efficiently yield a dominant population of states with masses significantly greater than the confinement scale and, in contrast to dark matter that is a fundamental particle, may allow the dominant form of dark matter to have high spin ( S≫3/2 ), whose discovery would be smoking gun evidence for dark nuclei.