TH Cosmo Coffee

Conversion of dark photons in the late-time Universe

by Kyrylo Bondarenko

Europe/Zurich
4/2-011 - TH common room (CERN)

4/2-011 - TH common room

CERN

40
Show room on map
Description

It is well known that dark photons can resonantly convert to normal photons if the effective mass of the photon is equal to the mass of a dark photon. Constraints on dark photons were put from dark-to-normal photon (in both directions) considering the conversion at high-redshift, almost homogeneous Universe. I will discuss the conversion at low redshifts that happens in the inhomogeneous Universe. For this, I use the data from 100 cMpc Eagle simulations. I will apply these results to the model by Pospelov et al [1803.07048], where dark photons are created from the decays of DM axions. This model was proposed as a possible explanation of EDGES anomaly in the 21cm signal. I will show that taking into account late time conversion allows excluding a large part of the parameter space of this model.