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arXiv · hep-lat/9801019

Thermodynamics of Lattice QCD with Chiral 4-Fermion Interactions

J. B. Kogut·J. -F. Lagae·D. K. Sinclair
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Abstract

We have studied lattice QCD with an additional, irrelevant 4-fermion interaction having a U(1)xU(1) chiral symmetry, at finite temperatures. Adding this 4-fermion term allowed us to work at zero quark mass, which would have otherwise been impossible. The theory with 2 massless staggered quark flavours appears to have a first order finite temperature phase transition at N_t=4 for the value of 4-fermion coupling we have chosen, in contrast to what is expected for 2-flavour QCD. The pion screening mass is seen to vanish below this transition, only to become massive and degenerate with the sigma (f_0) above this transition where the chiral symmetry is restored, as is seen by the vanishing of the chiral condensate.

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J. B. Kogut, J. -F. Lagae, D. K. Sinclair. 1998-01-19. Thermodynamics of Lattice QCD with Chiral 4-Fermion Interactions. https://doi.org/10.1103/physrevd.58.034504

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