Modifications on parameters of $Z(4430)$ in a dense medium

TL;DR

This paper investigates how the properties of the exotic tetraquark candidate $Z(4430)$ change in a dense medium, extending previous work on $Z_c(3900)$ to better understand their internal structure and behavior under extreme conditions.

Contribution

It provides the first detailed analysis of medium modifications on the mass, vector self-energy, and current coupling of the excited $Z(4430)$ state at high densities.

Findings

Mass decreases with increasing density.

Vector self-energy shows significant density dependence.

Results are relevant for experimental studies at high-density environments.

Abstract

The charmonium-like resonance $ Z_c(3900) $ and its excited state $ Z(4430) $ are among the particles that are serious candidates for double heavy tetraquarks. Calculations of different parameters associated with these states both in the vacuum and the medium with finite density are of great importance. Such investigations help us clarify their nature, internal quark-gluon organization and quantum numbers. In this accordance, we extend our previous analyses on the ground state $ Z_c(3900) $ to investigate the medium modifications on different parameters of the excited $ Z(4430) $ state. In particular, we calculate the mass, vector self-energy and current coupling of $ Z(4430) $ in terms of density, up to a density comparable to the density of the cores of massive neutron stars. The obtained results may help experimental groups aiming to study the behavior of exotic states at higher densities.