Dark matter seeping through dynamic gauge kinetic mixing

Abstract

We show for the first time that the loop-driven kinetic mixing between visible and dark Abelian gauge bosons can facilitate dark matter production in the early Universe by creating a 'dynamic' portal, which depends on the energy of the process. The required smallness of the strength of the portal interaction, suited for freeze-in, is justified by a suppression arising from the mass of a heavy vector-like fermion. The strong temperature sensitivity associated with the interaction is responsible for most of the dark matter production during the early stages of reheating.

Kaluza-Klein FIMP dark matter in warped extra-dimensions

“…Therefore, the exponent of the boost factor becomes (T max /T rh ) n−nc with n c ≡ 6 + 2 3−ω 1+ω , showing a strong dependence on the equation of state [67]. Subsequent papers have explored the impact of this boost factor in specific models [4,[70][71][72][73][74][75][76][77][78][79][80]. Finally, another way for enhancing the DM abundance occurs in cosmologies where inflation is followed by an epoch dominated by a fluid stiffer than radiation.…”

UV freeze-in in Starobinsky inflation

“…refs. [14][15][16][17][18][19][20][21][22][23][24][25][26]). Unlike IR freeze-in scenarios, where the bulk of the JCAP10(2020)021 DM abundance is produced at low scales, typically when the temperature of the SM thermal bath is of the order of the DM or the mediator mass, UV freeze-in is mostly effective at high temperatures.…”

FIMP Dark Matter in Clockwork/Linear Dilaton extra-dimensions

“…refs. [60,[69][70][71][72][73][74][75][76][77][78][79][80][81][82][83][84][85]). It would also be interesting to analyze in more detail the cosmology of the CW/LD scenario, in particular the feasibility of complete DM models with such low reheating temperatures as we have found.…”