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arXiv · 1205.6545

Strong-coupling Analysis of Parity Phase Structure in Staggered-Wilson Fermions

Tatsuhiro Misumi·Takashi Z. Nakano·Taro Kimura·Akira Ohnishi
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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.

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Tatsuhiro Misumi, Takashi Z. Nakano, Taro Kimura, Akira Ohnishi. 2012-05-30. Strong-coupling Analysis of Parity Phase Structure in Staggered-Wilson Fermions. https://doi.org/10.1103/physrevd.86.034501

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