D-term Enhancement in Spin-1 Top Partner Model

Supersymmetric models with extended electroweak gauge groups have the potential to enhance the Higgs quartic interaction through nondecoupling D-terms. We consider the D-term enhancement effect in a vector top partner model, where the quadratic divergence to the Higgs mass from the virtual top quark is canceled by its corresponding spin-1 superpartners. We are going to show that the model can predict a Higgs mass beyond the LEP bound, and is consistent with the precision electroweak constraints.