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arXiv · hep-ph/9803301

Anomalous Effective Lagrangian and Theta Dependence in QCD at Finite N_c

Igor Halperin·Ariel Zhitnitsky
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Abstract

We generalize the large N_c Di Vecchia-Veneziano-Witten (VVW) effective chiral Lagrangian to the case of finite N_c by constructing the anomalous effective Lagrangian for QCD. The latter is similar to its SUSY counterpart, and has a holomorphic structure. The VVW construction is then recovered, along with 1/N_c corrections, after integrating out the heavy "glueball" fields. A new mass formula for eta' meson in terms of QCD condensates is obtained. The picture of theta dependence in QCD for finite N_c is more complicated than the one predicted by the large N_c approach.

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Igor Halperin, Ariel Zhitnitsky. 1998-06-09. Anomalous Effective Lagrangian and Theta Dependence in QCD at Finite N_c. https://doi.org/10.1103/physrevlett.81.4071

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