Topological Portal to the Dark Sector

I will propose a topological portal interaction connecting quantum chromodynamics (QCD) with a dark QCD-like sector, present only for a unique dark coset structure SU(2)/SO(2) after confinement, which connects three QCD pions to two dark pions. Upon gauging QED, the topological interaction serves as the leading portal between the two sectors, providing an elegant self-consistent scenario of light thermal inelastic dark matter. The inherent antisymmetrization leads to diminished annihilations at later times and extremely suppressed direct detection. However, novel collider signatures involving boosted pions and missing energy offer tremendous prospects for discovery at Belle II. The talk is based on https://arxiv.org/abs/2401.09528 with Admir Greljo and Nudzeim Selimovic.