Cosmological Constraints on Very Dark Photons

Autoren: Josef Pradler, Anthony Fradette, Maxim Pospelov, Josef Pradler, Adam Ritz
Gruppe: Theorie DM
Kategorie: Reviewed Paper

We explore the cosmological consequences of kinetically mixed dark photons with a mass between 1 MeV and 10 GeV, and an effective electromagnetic fine structure constant as small as $10^{-38}$. We calculate the freeze-in abundance of these dark photons in the early Universe and explore the impact of late decays on BBN and the CMB. This leads to new constraints on the parameter space of mass $m_V$ vs kinetic mixing parameter $\kappa$.