2004/07/31 by L. Scorzato, Luigi Scorzato · 3 citations
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-lat
paper · pdf · doi:10.1140/epjc/s2004-01994-x
published as Eur.Phys.J. C37 (2004) 445-455 · 20 pages 40 figures, references updated, to be published in EPJC
arxiv created 2004/09/07 · openalex publication_date 2004/10/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/29
In the framework of Wilson Chiral Perturbation Theory, we study the effect induced by a twisted Wilson term, as it appears in Twisted Mass QCD (with 2 degenerate quarks). In particular we consider the vacuum orientation and the pion masses. The computations are done to NLO both in the mass and in the lattice spacing (i.e. to O(a2)). There are no restrictions on the relative size of lattice artifacts with respect to the physical mass, thus allowing, in principle, to bridge between the physical regime and the unphysical one, where lattice artifacts tend to dominate. The inclusion of O(a2) lattice artifacts can account for the splitting of degeneracy of the three pion masses. Moreover O(a2) terms are necessary to model non trivial behaviors of the vacuum orientation such as possible Aoki phases. It turns out that these last two phenomena are determined by the same constant.