Exploration of the MSSM with non-universal Higgs masses Original Research Article

We explore the parameter space of the minimal supersymmetric extension of the Standard Model (MSSM), allowing the soft supersymmetry-breaking masses of the Higgs multiplets, m1,2, to be non-universal (NUHM). Compared with the constrained MSSM (CMSSM) in which m1,2 are required to be equal to the soft supersymmetry-breaking masses m0 of the squark and slepton masses, the Higgs mixing parameter μ and the pseudoscalar Higgs mass mA, which are calculated in the CMSSM, are free in the NUHM model. We incorporate accelerator and dark matter constraints in determining allowed regions of the (μ,mA), (μ,M2) and (m1/2,m0) planes for selected choices of the other NUHM parameters. In the examples studied, we find that the LSP mass cannot be reduced far below its limit in the CMSSM, whereas mA may be as small as allowed by LEP for large tanβ. We present in Appendices A–D details of the calculations of neutralino–slepton, chargino–slepton and neutralino–sneutrino coannihilation needed in our exploration of the NUHM.