pseudo-Nambu-Goldstone boson Dark Matter

This project explores a dark matter model where a pseudo-Nambu-Goldstone boson (pNGB) arises as a viable dark matter candidate from the spontaneous and soft breaking of global symmetries, stabilized by a residual $\mathbb{Z}_3$ symmetry. The model introduces three complex scalar fields, singlets under the Standard Model gauge group, and charged under a dark $U(1)_V$ gauge symmetry. These features naturally suppress dark matter–nucleon scattering cross sections due to the pNGB nature.

In addition to conventional annihilation channels, the $\mathbb{Z}_3$ structure enables semi-annihilation processes, leading to new phenomenological signatures such as boosted dark matter (BDM). We analyze theoretical and experimental constraints, including relic abundance, Higgs invisible decay, and perturbative unitarity bounds. While the resulting BDM flux in neutrino detectors like DUNE is found to be below experimental sensitivity, the model provides a minimal and predictive framework for semi-annihilation-driven dark matter phenomenology.

See this related work for more details.