Dark Lepton Superfluid in Proto-Neutron Stars

Understand

We find that sub-GeV neutrino portal bosons that carry lepton number can condense inside a proto-neutron star (newly born neutron star).

• These bosons are produced copiously and form a Bose-Einstein condensate for a range of as yet unconstrained coupling strengths to neutrinos.
• The condensate is a lepton number superfluid with transport properties that differ dramatically from those encountered in ordinary dense baryonic matter.
• We discuss how this phase could alter the evolution of proto-neutron stars and comment on the implications for neutrino signals and nucleosynthesis.