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Register a new userConsistent treatment of axions in the weak chiral Lagrangian
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Authors
Martin Bauer
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We present a consistent implementation of weak decays involving an axion or axion-like particle in the context of an effective chiral Lagrangian. We argue that previous treatments of such processes have used an incorrect representation of the flavor-changing quark currents in the chiral theory. As an application, we derive model-independent results for the decays $K^-topi^- a$ and $pi^-to e^-bar u_e a$ at leading order in the chiral expansion and for arbitrary axion couplings and mass. In particular, we find that the $K^-topi^- a$ branching ratio is almost 40 times larger than previously estimated.
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