The phase structure of a chirally invariant lattice Higgs-Yukawa model

We consider a chirally invariant lattice Higgs-Yukawa model based on the Neuberger overlap operator D(ov). As a first step towards the eventual determination of Higgs mass bounds we present the phase structure of the model analytically in the large Nf-limit in the physically interesting region of the Yukawa coupling constant. We confront the analytically obtained phase diagram with corresponding HMC-simulations and find an excellent agreement at large values of Nf. In the opposite case the large Nf computation still gives a good qualitative description of the phase diagram. We also present first and very preliminary results on the Higgs upper bound at one selected cut-off Λ. (orig.)