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K -> pi pi and a light scalar meson

J. C. R. Bloch·M. A. Ivanov·T. Mizutani·C. D. Roberts·S. M. Schmidt
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Abstract

We explore the Delta-I= 1/2 rule and epsilon'/epsilon in K -> pi pi transitions using a Dyson-Schwinger equation model. Exploiting the feature that QCD penguin operators direct K^0_S transitions through 0^{++} intermediate states, we find an explanation of the enhancement of I=0 K -> pi pi transitions in the contribution of a light sigma-meson. This mechanism also affects epsilon'/epsilon.

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J. C. R. Bloch, M. A. Ivanov, T. Mizutani, C. D. Roberts, S. M. Schmidt. 1999-10-11. K -> pi pi and a light scalar meson. https://doi.org/10.1103/physrevc.62.025206

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