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arXiv · 2603.16266

Lattice QCD study of the $K^*(892)$ resonance at the physical point

Qu-Zhi Li·Chuan Liu·Liuming Liu·Peng Sun·Jia-Jun Wu·Zhiguang Xiao·Han-Qing Zheng
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Abstract

We present a lattice QCD study of the $K^*(892)$ resonance using eight $N_f=2+1$ Wilson-Clover ensembles with three lattice spacings and six pion masses ranging from 135 to 320 MeV. For each ensemble, a large number of finite volume energy levels in the $P$-wave $K\pi$ channel are determined. The energy dependence of the scattering phase shift is then obtained from L\"uscher's finite-volume method. To systematically assess parametrization dependence, the amplitude is described using three different models, which yield consistent results. The resulting phase shifts show a clear resonant behavior for all ensembles, and the corresponding $K^*(892)$ resonance pole is identified on the second Riemann sheet in the complex energy plane. The pole positions are extrapolated to the physical pion mass and the continuum limit, yielding a $K^*(892)$ resonance located at $\sqrt{s_0} = [883(22)-i20(13)]\mathrm{MeV}$, which is in excellent agreement with the experimental value. This study provides a first-principles QCD determination of the $K^*(892)$ mass and width with controlled systematic uncertainties.

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Qu-Zhi Li, Chuan Liu, Liuming Liu, Peng Sun, Jia-Jun Wu, Zhiguang Xiao, Han-Qing Zheng. 2026-03-17. Lattice QCD study of the $K^*(892)$ resonance at the physical point. https://arxiv.org/abs/2603.16266

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