Implications of heavy quark spin symmetry on heavy meson hadronic molecules

TL;DR

This paper explores how heavy quark spin symmetry influences heavy meson molecules, predicting new states and providing methods to test their existence through specific decay channels and invariant mass spectra.

Contribution

It introduces a framework based on heavy quark spin symmetry to predict new heavy meson molecules and suggests experimental tests for these states.

Findings

Predicted an 'f_0(980) bound state as a partner to Y(4660).

Calculated decay modes and widths for the predicted states.

Proposed experimental search strategies in B meson decays.

Abstract

In recent years, many heavy mesons and charmonia were observed which do not fit in the conventional quark model expectations. Some of them are proposed to be hadronic molecules. Here we investigate the consequences of heavy quark spin symmetry on these heavy meson hadronic molecules. Heavy quark spin symmetry enables us to predict new heavy meson molecules and provides us with a method to test heavy meson molecule assumptions of some newly observed states. In particular, we predict an \eta_c'f_0(980) bound state as the spin-doublet partner of the Y(4660) proposed as a \psi'f_0(980) bound state with a mass of 4616^{+5}_{-6} MeV and the prominent decay mode \eta_c'\pi \pi. The width is predicted to be \Gamma(\eta_c'\pi\pi)=60\pm30 MeV. The pi^+\pi^- invariant mass spectrum and the line shape are calculated. We suggest to search for this state in B^{\pm}-->\eta_c'K^{\pm}\pi^+\pi^-, whose branching fraction is expected to be large.