Analysis of Y(4660) and related bound states with QCD sum rules

TL;DR

This paper uses QCD sum rules to analyze the mass of the Y(4660) state as a bound state of $\\psi'f_0(980)$ and predicts masses for related heavy quark bound states, aligning with experimental data.

Contribution

It is the first to apply QCD sum rules to study Y(4660) as a specific bound state and predict masses of related states considering SU(3) and heavy quark symmetries.

Findings

Mass of Y(4660) is consistent with experimental data.

Predicted masses for $\\psi'\sigma$ and $\\Upsilon'\f_0(980)$ bound states.

Abstract

In this article, we take the vector charmonium-like state Y(4660) as a $\psi'f_0(980)$ bound state (irrespective of the hadro-charmonium and the molecular state) tentatively, study its mass using the QCD sum rules, the numerical value $M_Y=4.71\pm0.26 \rm{GeV}$ is consistent with the experimental data. Considering the SU(3) symmetry of the light flavor quarks and the heavy quark symmetry, we also study the bound states $\psi'\sigma(400-1200)$, $\Upsilon'"f_0(980)$ and $\Upsilon"'\sigma(400-1200)$ with the QCD sum rules, and make reasonable predictions for their masses.