Masses of fully heavy tetraquarks $QQ \bar Q \bar Q$ in an extended relativized quark model

TL;DR

This paper predicts the mass spectra of fully heavy tetraquarks using an extended relativized quark model, suggesting possible states around 6.4 and 6.9 GeV, and discusses their strong decay modes.

Contribution

It introduces an extended relativized quark model to estimate masses and decay properties of fully heavy tetraquarks, providing predictions for experimental verification.

Findings

Broad structure around 6.4 GeV likely contains ground $cc\bar c\bar c$ states.

Narrow structure near 6.9 GeV may be the first radial excitation.

Strong decay channels into heavy quarkonium pairs are qualitatively analyzed.

Abstract

Inspired by recent measurement of possible fully charmed tetraquarks in LHCb Collaboration, we investigate the mass spectra of fully heavy tetraquarks $QQ \bar Q \bar Q$ in an extended relativized quark model. Our estimations indicate that the broad structure around 6.4 GeV should contain one or more ground $cc \bar c \bar c$ tetraquark states, while the narrow structure near 6.9 GeV can be categorized as the first radial excitation of $cc \bar c \bar c$ system. Moreover, with the wave functions of the tetraquarks and mesons, the strong decays of tetraquarks into heavy quarkonium pair are qualitatively discussed, which can be further checked by the LHCb and CMS Collaborations.