We consider the possibility of an interaction in the dark sector in the presence of massive neutrinos and study the observational constraints on three different scenarios of massive neutrinos using the most recent cosmic microwave background anisotropy data in combination with type Ia supernovae, baryon acoustic oscillations, and Hubble parameter measurements. When a sterile neutrino is introduced into the interacting dark sector scenario in addition to the standard model prediction of neutrinos, we find that the coupling parameter is nonzero at a $2\sigma$ confidence level. The interaction model with a sterile neutrino is also found to be a promising one to alleviate the current tension on the Hubble constant. We do not find the evidence for a coupling in the dark sector when the possibility of a sterile neutrino is discarded.

• Received 10 August 2016

DOI:https://doi.org/10.1103/PhysRevD.94.123511