---
abstract: 'We study strong-coupling lattice QCD with staggered-Wilson fermions, with emphasis on discrete symmetries and possibility of their spontaneous breaking. We perform hopping parameter expansion and effective potential analyses in the strong-coupling limit. From gap equations we find nonzero pion condensate in some range of a mass parameter, which indicates existence of the parity-broken phase in lattice QCD with staggered-Wilson fermions. We also find massless pions and PCAC relations around second-order phase boundary. These results suggest that we can take a chiral limit by tuning a mass parameter in lattice QCD with staggered-Wilson fermions as with the Wilson fermion.'
author:
- Tatsuhiro Misumi
- 'Takashi Z. Nakano'
- Taro Kimura
- Akira Ohnishi
title: |
     Strong-coupling Analysis of Parity Phase Structure\
    in Staggered-Wilson Fermions 
---

Introduction {#sec:Intro}
============

Since the dawn of lattice field theory [@Wil], the doubling problem of fermions has been a notorious obstacle to lattice simulations. Among several prescriptions for this problem, the Wilson fermion simply bypasses the no-go theorem [@NN] by introducing a species-splitting mass term into the naive lattice fermion. This Wilson term is regarded as one example of “flavored-mass terms" which split original 16 fermion species into plural branches [@CKM1; @CKM12]. It has 