Nonrelativistic Treatment of Fully-Heavy Tetraquarks as Diquark-Antidiquark States

TL;DR

This paper uses a nonrelativistic diquark-antidiquark model with specific potentials to estimate the masses of fully-heavy tetraquarks, providing predictions that can guide experimental searches.

Contribution

It introduces a nonrelativistic model with Hulthen and confining potentials to calculate masses of fully-heavy tetraquarks, including excited states, which is a novel approach in this context.

Findings

Ground state masses are above decay thresholds, implying broad states.

Excited states are below two-meson thresholds, suggesting narrower states.

Predicted masses can assist experimental identification of tetraquarks.

Abstract

The goal of the present work is to obtain a reliable estimate of the masses of the ground and radially excited states of fully-heavy tetraquark systems. In order to do this, we use a nonrelativistic model of tetraquarks which are assumed to be compact and consist of diquark-antidiquark pairs. This nonrelativistic model is composed of Hulthen potential, a linear confining potential and spin-spin interaction. We computed ground, first, and second radially excited $cc\bar{c}\bar{c}$ and $bb\bar{b}\bar{b}$ tetraquark masses. It was found that predicted masses of ground states of $cc\bar{c}\bar{c}$ and $bb\bar{b}\bar{b}$ tetraquarks are significantly higher than the thresholds of the fall-apart decays to the lowest allowed two-meson states. These states should be broad and are thus difficult to observe experimentally. First radially excited states are considerably lower than their corresponding (2S-2S) two-meson thresholds. We hope that our study may be helpful to the experimental search for ground and excited $cc\bar{c}\bar{c}$ and $bb\bar{b}\bar{b}$ tetraquark states.