Gravitational Vector Dark Matter

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 ${\mathrm{\Lambda }}_{\mathrm{D}\mathrm{M}}$ giving bound states with typical lifetimes $\tau \sim M_{\rm Pl}^4/\Lambda^5_{\rm DM}$thatcanbeDMcandidatesif$\Lambda_{\rm 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 $\tau \sim M_{\mathrm{P}\mathrm{l}}^8\mathrm{/}{\mathrm{\Lambda }}_{\mathrm{D}\mathrm{M}}^9$; even longer lifetimes $\tau= (M_{\rm Pl}/\Lambda_{\rm DM})^{2N-4}/\Lambda_{\rm DM}$arisefromSO$(N)$theorieswith$N \ge 8$,andpossiblyfrom$F_4$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 ${\mathrm{\Lambda }}_{\mathrm{D}\mathrm{M}}\gtrsim {10}^{10}$ GeV.