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arXiv · 1710.01557

The elastic $I=3/2$ $p$-wave nucleon-pion scattering amplitude and the $\Delta(1232)$ resonance from $N_{\mathrm{f}}=2+1$ lattice QCD

Christian Walther Andersen·John Bulava·Ben Hörz·Colin Morningstar
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Abstract

We present the first direct determination of meson-baryon resonance parameters from a scattering amplitude calculated using lattice QCD. In particular, we calculate the elastic $I=3/2$, $p$-wave nucleon-pion amplitude on a single ensemble of $N_{\mathrm{f}}=2+1$ Wilson-clover fermions with $m_{\pi}=280\mathrm{MeV}$ and $m_{K}=460\mathrm{MeV}$. At these quark masses, the $\Delta(1232)$ resonance pole is found close to the $N-\pi$ threshold and a Breit-Wigner fit to the amplitude gives $g^{\mathrm{BW}}_{\Delta N\pi}=19.0(4.7)$ in agreement with phenomenological determinations.

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Christian Walther Andersen, John Bulava, Ben Hörz, Colin Morningstar. 2017-10-04. The elastic $I=3/2$ $p$-wave nucleon-pion scattering amplitude and the $\Delta(1232)$ resonance from $N_{\mathrm{f}}=2+1$ lattice QCD. https://doi.org/10.1103/physrevd.97.014506

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