The lightest $D_0^\ast$ resonance from lattice QCD

TL;DR

This paper uses lattice QCD to study the elastic scattering of D pi mesons, revealing a very light D0* resonance with a mass around 2200 MeV, significantly below experimental values, and compares these findings with previous studies and experimental data.

Contribution

It provides the first lattice QCD determination of the lightest D0* resonance, including its mass and width, and compares these results with experimental data and chiral perturbation theory.

Findings

Resonance mass around 2200 MeV

Width approximately 400 MeV

Results significantly below experimental D0* mass

Abstract

We recently presented elastic $I=1/2$ $D\pi$ scattering from lattice QCD at $m_{\pi} = 239$ MeV. The amplitude features a pole corresponding to a mass $m \approx 2200$ MeV and a width $\Gamma \approx 400$ MeV. The results were compared to an earlier study at a higher pion mass and to a similar study in the charm-strange sector. In this contribution to LATTICE2021 I summarize these results and compare them with experiment, based on the values reported by the particle data group. Our result lies significantly below the experimental $D_0^\ast$. I also relate our findings to recent studies in chiral perturbation theory. Based on work presented in JHEP2021(7),123 for the Hadron Spectrum Collaboration.