3-3-1-1 model for dark matter

Original · EN

We show that the SU(3)C X SU(3)ₗ X U(1)ₓ (3-3-1) model of strong and electroweak interactions can naturally accommodate an extra U(1)ₙ symmetry behaving as a gauge symmetry. Resulting theory based on SU(3)C X SU(3)ₗ X U(1)ₓ X U(1)ₙ (3-3-1-1) gauge symmetry realizes B-L=-(2/√3)T₈+N as a charge of SU(3)ₗ X U(1)ₙ. Consequently, a residual symmetry, W-parity, resulting from broken B-L in similarity to R-parity in supersymmetry is always conserved and may be unbroken. There is a specific fermion content recently studied in which all new particles that have wrong lepton-numbers are odd under W-parity, while the standard model particles are even. Therefore, the lightest wrong-lepton particle (LWP) responsible for dark matter is naturally stabilized. We explicitly show that the non-Hermitian neutral gauge boson (X⁰) as LWP cannot be a dark matter. However, the LWP as a new neutral fermion (Nᵣ) can be dark matter if its mass is in range 1.9 TeV ≤ mₙᵣ ≤ 2.5 TeV, provided that the new neutral gauge boson (Z') mass satisfies 2.2 TeV ≤ mZ' ≤ 2.5 TeV. Moreover, the scalar dark matter candidate (H'≃ η₃) which has traditionally been studied is only stabilized by W-parity. All the unwanted interactions and vacuums as often encountered in the 3-3-1 model are naturally suppressed. And, the standing issues on tree-level flavor changing neutral currents and CPT violation also disappear.