SINGLET SUPERFIELD EXTENSION OF THE MINIMAL SUPERSYMMETRIC STANDARD MODEL WITH PECCEI–QUINN SYMMETRY AND A LIGHT PSEUDOSCALAR HIGGS BOSON AT THE LHC

Abstract

Motivated by the μ-problem and the axion solution to the strong CP-problem, we extend the MSSM with one more chiral singlet field X ew . The underlying PQ-symmetry allows only one more renormalizable term X ew Hu Hd in the superpotential. The spectrum of the Higgs system includes a light pseudoscalar aX (in addition to the standard CP-even Higgs boson), predominantly decaying to two photons: aX →γγ. Both Higgs bosons might be in the range accessible to current LHC experiments.