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

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.

10 Pages, 7 Figures and 2 Tables