Hadron spectrum of QCD with one quark flavor

The latest results of an ongoing project for the lattice simulation of QCD with a single quark flavor are presented. The Symanzik tree-level-improved Wilson action is adopted in the gauge sector and the (unimproved) Wilson action for the fermion. Results from new simulations with one step of Stout-smearing (ρ = 0.15) in the fermion action are discussed. The one-flavor theory is simulated by a polynomial hybrid Monte Carlo algorithm (PHMC) at β = 4.0 corresponding to a = 0.13fm, on 163 · 32 and 243 · 48 lattices; the box-size is L ≃ 2.1fm and L ≃ 3.1fm, respectively. At the lightest simulated quark mass the (partially quenched) pion mass is ∼ 300 MeV. The masses of the lightest bound states are computed, including the flavor singlet scalar and pseudoscalar mesons σs and ηs, the scalar glueball 0++, and the ∆++ baryon. Relics of SUSY in the mass spectrum, expected from a large Nc orientifold equivalence with the N =1 supersymmetric YangMills theory, are discussed.