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arXiv · 2102.03059

Extracting the low-energy constant $L_0^r$ at three flavors from pion-kaon scattering

Chaitra Kalmahalli Guruswamy·Ulf-G. Meißner·Chien-Yeah Seng
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Abstract

Based on our analysis of the contributions from the connected and disconnected contraction diagrams to the pion-kaon scattering amplitude, we provide the first determination of the only free low-energy constant at $\mathcal{O}(p^4)$, known as $L_0^r$, in SU$(4|1)$ Partially-Quenched Chiral Perturbation Theory using the data from the Extended Twisted Mass Collaboration, $L_0^r(\mu=M_\rho) = 0.77(20)(25)(7)(7)(2)\cdot 10^{-3}$. The theory uncertainties originate from the unphysical scattering length, the physical low-energy constants, the higher-oder chiral corrections, the (lattice) meson masses and the pion decay constant, respectively

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Chaitra Kalmahalli Guruswamy, Ulf-G. Meißner, Chien-Yeah Seng. 2021-02-05. Extracting the low-energy constant $L_0^r$ at three flavors from pion-kaon scattering. https://doi.org/10.1088/1572-9494%2Fac6d50

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