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Mesonic Wavefunctions in the three-dimensional Gross-Neveu model

S. J. Hands·J. B. Kogut·C. G. Strouthos
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Abstract

We present results from a numerical study of bound state wavefunctions in the (2+1)-dimensional Gross-Neveu model with staggered lattice fermions at both zero and nonzero temperature. Mesonic channels with varying quantum numbers are identified and analysed. In the strongly coupled chirally broken phase at T=0 the wavefunctions expose effects due to varying the interaction strength more effectively than straightforward spectroscopy. In the weakly coupled chirally restored phase information on fermion - antifermion scattering is recovered. In the hot chirally restored phase we find evidence for a screened interaction. The T=0 chirally symmetric phase is most readily distinguished from the symmetric phase at high T via the fermion dispersion relation.

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S. J. Hands, J. B. Kogut, C. G. Strouthos. 2002-01-21. Mesonic Wavefunctions in the three-dimensional Gross-Neveu model. https://doi.org/10.1103/physrevd.65.114507

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