Gravitational vector Dark Matter

A bstract A new dark sector consisting of a pure non-abelian gauge theory has no renormalizable interaction with SM particles, and can thereby realise gravitational Dark Matter (DM). Gauge interactions confine at a scale Λ DM giving bound states with typical lifetimes τ ∼ M P 1 4 / Λ DM 5 that can be DM candidates if Λ DM is below 100 TeV. Furthermore, accidental symmetries of group-theoretical nature produce special gravitationally stable bound states. In the presence of generic Planck-suppressed operators such states become long-lived: SU( N ) gauge theories contain bound states with τ ∼ M P 1 8 / Λ DM 9 ; even longer lifetimes τ = ( M Pl /Λ DM ) 2 N− 4 /Λ DM arise from SO( N ) theories with N ≥ 8, and possibly from F 4 or E 8 . We compute their relic abundance generated by gravitational freeze-in and by inflationary fluctuations, finding that they can be viable DM candidates for Λ DM ≳ 10 10 GeV.