Nonlinear supersymmetry and goldstino couplings to the MSSM

We briefly review the nonlinear supersymmetry formalisms in the standard realization and superfield methods. We then evaluate the goldstino couplings to the minimal supersymmetric standard model (MSSM) superfields and discuss their phenomenological consequences. These relate to the tree-level Higgs mass and to invisible Higgs- and $Z$-boson decays. The Higgs mass is increased from its MSSM tree-level value and brought above the LEP$2$ mass bound for a low scale of supersymmetry breaking $\sqrt{f}\sim2$ TeV to $7$ TeV. The invisible decay rates of the Higgs and $Z$ bosons into goldstino and neutralino are computed and shown to bring stronger constraints on $f$ than their decays into goldstino pairs, which are subleading in $1/f$.