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$K^{+}\toπ^{+}π^{0}$ decays at next-to-leading order in the chiral expansion on finite volumes

C. -J. D. Lin·G. Martinelli·E. Pallante·C. T. Sachrajda·G. Villadoro
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Abstract

We present the ingredients for determining $K^{+}\toπ^{+}π^{0}$ matrix elements via the combination of lattice QCD and chiral perturbation theory ($χ$PT). By simulating these matrix elements at unphysical kinematics, it is possible to determine all the low-energy constants (LECs) for constructing the physical $K^{+}\toπ^{+}π^{0}$ amplitudes at next-to-leading order (NLO) in the chiral expansion. In this work, the one-loop chiral corrections are calculated for arbitrary meson four-momenta, in both $χ$PT and quenched $χ$PT (q$χ$PT), and the finite-volume effects are studied.

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BibTeXRIS

C. -J. D. Lin, G. Martinelli, E. Pallante, C. T. Sachrajda, G. Villadoro. 2002-09-03. $K^{+}\toπ^{+}π^{0}$ decays at next-to-leading order in the chiral expansion on finite volumes. https://doi.org/10.1016/s0920-5632(03)01561-5

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