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Register a new userDark matter seeping through dynamic gauge kinetic mixing
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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.
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