Low-energy $DD$ scattering in lattice QCD

TL;DR

This paper reports the first lattice QCD calculation of $DD$ scattering for specific quantum numbers, revealing weak repulsion or attraction depending on the channel, and providing scattering parameters extrapolated to physical pion mass.

Contribution

It introduces the first lattice QCD study of single-channel $DD$ scattering with detailed analysis of scattering parameters for different quantum channels.

Findings

Weak repulsive interaction in the $1(0^+)$ channel.

Slightly attractive interaction in the $0(1^-)$ channel.

Extrapolated scattering length and effective range at physical pion mass.

Abstract

We present the first lattice QCD calculation of single-channel $DD$ scattering with quantum numbers $I(J^P)=1(0^+)$ and $0(1^-)$. The calculation is performed on the $2+1$ flavor Wilson-Clover ensembles with a lattice spacing $a\simeq 0.077$ fm and two different pion masses, $m_{\pi}\simeq207$ and $305$ MeV. The scattering parameters are determined using the L\"uscher's finite volume method. Our results indicate weak repulsive interaction in the $1(0^+)$ channel and slightly attractive interaction in the $0(1^-)$ channel. The $S$-wave isovector $DD$ scattering length and effective range, extrapolated to the physical pion mass, are $(-0.26\pm0.05)$ fm and $(-5.5\pm2.1)$ fm, respectively.