Dark matter in the classically conformal B-L model

TL;DR

This paper explores a classically conformal B-L extended Standard Model where a Z_2 parity stabilizes right-handed neutrino dark matter, analyzing its relic abundance, mass relations, and detection prospects within a framework of symmetry breaking via the Coleman-Weinberg mechanism.

Contribution

It introduces a novel conformal B-L model with a Z_2 parity stabilizing dark matter and derives its phenomenological implications, including mass relations and detection prospects.

Findings

Dark matter relic abundance can match observations near resonance regions.

Masses of Higgs, Z', and dark matter are interconnected and consistent with experimental data.

Predicted spin-independent cross section for dark matter-nucleon interactions informs future searches.

Abstract

When the classically conformal invariance is imposed on the minimal gauged B-L extended Standard Model (SM), the B-L gauge symmetry is broken by the Coleman-Weinberg mechanism naturally at the TeV scale. Introducing a new Z_2 parity in the model, we investigate phenomenology of a right-handed neutrino dark matter whose stability is ensured by the parity. We find that the relic abundance of the dark matter particle can be consistent with the observations through annihilation processes enhanced by resonances of either the SM Higgs boson, the B-L Higgs boson or the B-L gauge boson (Z' boson). Therefore, the dark matter mass is close to half of one of these boson masses. Due to the classically conformal invariance and the B-L gauge symmetry breaking via the Coleman-Weinberg mechanism, Higgs boson masses, Z' boson mass and the dark matter mass are all related, and we identify the mass region to be consistent with experimental results. We also calculate the spin-independent cross section of the dark matter particle off with nucleon and discuss implications for future direct dark matter search experiments.