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arXiv · 0906.4852

Chiral perturbation theory in a theta vacuum

Sinya Aoki·Hidenori Fukaya
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Abstract

We consider chiral perturbation theory (ChPT) with a non-zero theta term. Due to the CP violating term, the vacuum of chiral fields is shifted to a non-trivial element on the SU(N_f) group manifold. The CP violation also provides mixing of different CP eigenstates, between scalar and pseudoscalar, or vector and axialvector operators. We investigate upto O(theta^2) effects on the mesonic two point correlators of ChPT to the one-loop order. We also address the effects of fixing topology, by using saddle point integration in the Fourier transform with respect to theta.

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Sinya Aoki, Hidenori Fukaya. 2010-03-08. Chiral perturbation theory in a theta vacuum. https://doi.org/10.1103/physrevd.81.034022

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