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arXiv · 1605.07738

One-loop Chiral Perturbation Theory with two fermion representations

Thomas DeGrand·Maarten Golterman·Ethan T. Neil·Yigal Shamir
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Abstract

We develop Chiral Perturbation Theory for chirally broken theories with fermions in two different representations of the gauge group. Any such theory has a non-anomalous singlet $U(1)_A$ symmetry, yielding an additional Nambu-Goldstone boson when spontaneously broken. We calculate the next-to-leading order corrections for the pseudoscalar masses and decay constants, which include the singlet Nambu-Goldstone boson, as well as for the two condensates. The results can be generalized to more than two representations.

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Thomas DeGrand, Maarten Golterman, Ethan T. Neil, Yigal Shamir. 2016-05-25. One-loop Chiral Perturbation Theory with two fermion representations. https://doi.org/10.1103/physrevd.94.025020

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