Qualities of the axion and LSP in Pati-Salam unification with Z4R x ZN symmetry

In this paper we construct supersymmetric Pati-Salam (PS) models containing the minimal supersymmetric standard model and an invisible axion. The models include two discrete symmetries, Z(4)(R) x Z(N), which maintain the quality of the accidental Peccei-Quinn (PQ) symmetry and thus the solution to the strong CP problem. We require that the discrete anomaly conditions are satisfied for both Z(4)(R) x G(PS)(2) and Z(N) x G(PS)(2). The vacuum expectation value of the PQ field spontaneously breaks all the discrete symmetries. R-parity is violated if any of the PQ field(s) has an odd charge under Z(4)(R). We present two explicit models which we refer to as a minimal model where R-parity violation is extremely suppressed, and a nonminimal model where R-parity violation is significant. In the latter model, the neutralino becomes unstable even if it is the lightest supersymmetric particle (LSP), and, in addition, there are new low-energy vectorlike states. In both examples, R-parity violation is sufficiently suppressed such that the proton is stable.

Automated summary

In this paper, supersymmetric Pati-Salam models containing the minimal supersymmetric standard model and an invisible axion are constructed. The models include two discrete symmetries, Z(4)(R) x Z(N), and R-parity violation is significantly suppressed in one model but significant in another.