Status of quarkonia - like negative and positive parity states in a relativistic confinement scheme

TL;DR

This paper investigates the properties of quarkonia-like states in charm and bottom sectors using a relativistic Dirac formalism with linear confinement, aiming to identify and characterize various states including mixed P-wave and S-D wave configurations.

Contribution

It introduces a relativistic approach to compute mass spectra and decay properties of quarkonia-like states, providing insights into their structure and possible identification of unexplained states.

Findings

X(4140) as a P-wave admixture in charmonium

X(4630) and X(4660) as S-D wave admixtures

Predicted decay widths for mixed states

Abstract

Properties of quarkonia - like states in the charm and bottom sector have been studied in the frame work of relativistic Dirac formalism with a linear confinement potential. We have computed the mass spectroscopy and decay properties (vector decay constant and leptonic decay width) of several quarkonia - like states. Present study is also intended to identify some of the unexplained states as mixed P-wave and mixed S-D wave states of Charmonia and Bottomonia. The results indicate that the X(4140) state can be an admixture of two P states of charmonium. And the charmonium like states X(4630) and X(4660) are the admixed state of S - D waves. Similarly, the $X(10610)$ state recently reported by Belle II can be a mixed P - states of bottomonium. In the relativistic framework we have computed vector decay constant and the leptonic decay width for S wave charmonium and bottomonium. The leptonic decay width for the $J^{PC} = 1^{--}$ mixed states are also predicted. Further, both the masses and the leptonic decay width are considered for the identification of the quarkonia-like states.