The hadronic decay of vector charmonium

TL;DR

This paper introduces a computationally efficient lattice-based method using a narrow-width approximation to determine the hadronic decay parameters of vector charmonium, specifically the decay of $ ext{psi}(3770)$ into D-mesons, with results aligning with experimental data.

Contribution

The study presents an alternative lattice approach employing a narrow-width approximation to extract decay parameters, reducing computational complexity compared to traditional methods.

Findings

Results are compatible with experimental measurements.

Lattice simulations were performed at $m_\pi \sim 440$ MeV and $a\sim 0.066$ fm.

Analytical interpretation using the ${}^3P_0$ quark model was provided.

Abstract

The extraction of decay parameters using lattice techniques is a computationally expensive task, requiring several volumes and group irreps to relate the spectrum on a lattice simulation to the infinite volume scattering. In this project we employ an alternative method based on a narrow-width approximation to extract the hadronic mixing $<\bar{D}D|\psi(3770)>$, which is needed to compute the decay $\Gamma(\psi(3770)\to\bar{D}D)$ between the second excited state of vector charmonium and a pair of $D$-mesons in a $p$-wave. We carry out our lattice simulations on two CLS ensembles at $m_\pi \sim 440~\text{MeV}$ and $a\sim 0.066~\text{fm}$ and obtain results compatible with experiment. Furthermore, we interpret our results analytically using the ${}^3P_0$ quark model.