Feb 9, 2021
A warped scalar portal to fermionic dark matter
Posted by Saúl Morales Rodriguéz in categories: cosmology, particle physics
We argue that extensions of the SM with a warped extra dimension, together with a new $${\mathbb {Z}}_2$$ Z 2-odd scalar singlet, provide a natural explanation not only for the hierarchy problem but also for the nature of fermion bulk masses and the observed dark matter relic abundance. In particular, the Kaluza-Klein excitations of the new scalar particle, which is required to naturally obtain fermion bulk masses through Yukawa-like interactions, can be the leading portal to any fermion propagating into the bulk of the extra dimension and playing the role of dark matter. Moreover, such scalar excitations will necessarily mix with the Higgs boson, leading to modifications of the Higgs couplings and branching ratios, and allowing the Higgs to mediate the coannihilation of the fermionic dark matter.