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arXiv · hep-ph/9608255

U(1) Axial Symmetry and Correlation Functions in the High Temperature Phase of QCD

Michael C. Birse·Thomas D. Cohen·Judith A. McGovern
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Abstract

Simple group-theoretical arguments are used to demonstrated that in the high temperature (chirally restored) phase of QCD with N massless flavours, all n-point correlation functions of quark bilinears are invariant under U(1) axial transformations provided n < N. In particular this implies that the two-point correlation function in the eta' channel is identical to that in the pion channel for N > 2. Unlike previous work, this result does not depend on the topological properties of QCD and can be formulated without explicit reference to functional integrals.

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Michael C. Birse, Thomas D. Cohen, Judith A. McGovern. 1996-08-07. U(1) Axial Symmetry and Correlation Functions in the High Temperature Phase of QCD. https://doi.org/10.1016/0370-2693(96)01151-3

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