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arXiv · 1910.10418

Meson interactions at large $N_c$ from Lattice QCD

Fernando Romero-López·Andrea Donini·Pilar Hernández·Carlos Pena
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Abstract

We report on the computation of the scaling of QCD observables with the number of colours, $N_c$. For this, we use dynamical configurations with four active flavours, $N_f=4$, and values of $N_c=3-6$. We study the meson masses and decay constants, and compute the leading and subleading contributions to the Low Energy Constants (LECs) of the chiral Lagrangian. We also explore $\pi \pi$ scattering in the $I=2$ channel, and compute the $K \to \pi $ weak decay matrix elements. We comment on the relation of the latter to $K \to \pi\pi$ processes and the $\Delta I=1/2$ rule.

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Fernando Romero-López, Andrea Donini, Pilar Hernández, Carlos Pena. 2019-10-23. Meson interactions at large $N_c$ from Lattice QCD. https://arxiv.org/abs/1910.10418

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