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arXiv · 2311.03903

Study of the pion-mass dependence of $\rho$-meson properties in lattice QCD

Kang Yu·Yan Li·Jia-Jun Wu·Derek B. Leinweber·Anthony W. Thomas
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Abstract

We collect spectra extracted in the $I=\ell=1$ $\pi\pi$ sector provided by various lattice QCD collaborations and study the $m_\pi$ dependence of $\rho$-meson properties using Hamiltonian Effective Field Theory (HEFT). In this unified analysis, the coupling constant and cutoff mass, characterizing the $\rho - \pi \pi$ vertex, are both found to be weakly dependent on $m_\pi$, while the mass of the bare $\rho$, associated with a simple quark-model state, shows a linear dependence on $m_\pi^2$. Both the lattice results and experimental data can be described well. Drawing on HEFT's ability to describe the pion mass dependence of resonances in a single formalism, we map the dependence of the phase shift as a function of $m_\pi$, and expose interesting discrepancies in contemporary lattice QCD results.

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Kang Yu, Yan Li, Jia-Jun Wu, Derek B. Leinweber, Anthony W. Thomas. 2023-11-07. Study of the pion-mass dependence of $\rho$-meson properties in lattice QCD. https://arxiv.org/abs/2311.03903

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