The strong decay patterns of Z${}_c$ and Z${}_b$ states in the relativized quark model

Employing the relativized quark model and the quark-interchange model, we investigate the decay of the charged heavy quarkonium-like states Z${}_c$(3900), Z${}_c$(4020), Z${}_c$(4430), Z${}_b$(10610) and Z${}_b$(10650) into the ground and radially excited heavy quarkonia via emitting a pion meson. The Z${}_c$ and Z${}_b$ states are assumed to be hadronic molecules composed of open-flavor heavy mesons. The calculated decay ratios can be compared with the experimental data, which are useful in judging whether the molecule state assignment for the corresponding Z${}_c$ or Z${}_b$ state is reasonable or not. The theoretical framework constructed in this work will be helpful in revealing the underlying structures of some exotic hadrons.