More hidden heavy quarkonium molecules and their discovery decay modes

Abstract

To validate the molecular description of the observed Z b (10610)/Z b (10650) and Z c (3900)/Z c (4025), it is valuable to investigate their counterparts, denoted as Z (′) QV in this work, and the corresponding decay modes. In this work, we present an analysis of the Z (′) QV using flavor symmetry. We also use the effective Lagrangian based on the heavy quark symmetry to explore the rescattering mechanism and calculate the partial widths for the isospin conserved channels Z (′) QV → η Q V . The predicted partial widths are of an order of MeV for Z QV → η Q V , which correspond to branching ratios of the order of 10 −2 ∼ 10 −1 .For Z ′ QV → η Q V , the partial widths are a few hundreds of keV and the branching ratios are about 10 −3 . Future experimental measurements can test our predictions on the partial widths and thus examine the molecule description of heavy quarkoniumlike exotic states.

Probing the nature ofZc(′)states via theη

“…While this work was written up, a paper discussing the decays Z ( ) c → η c ρ in an Effective Lagrangian approach appeared [26], quite in agreement with our results.…”

Production of the Zb(′) states from the ϒWu1, Chen2, Guo3 2019Phys. Rev. D162100View full textAdd to dashboardCite

“…Moreover, their quantum numbers allow them to couple to a pair of bottom and anti-bottom ground state mesons in S-waves. These features suggest to consider the Z b and Z 0 b as the deuteronlike molecular states composed of B ÃB and B ÃBÃ , respectively [24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40]. In this scenario, the bb pairs in both Z b and Z 0 b are mixtures of a spintriplet and a spin-singlet, and thus the observations with similar rates of the Z ð0Þ b in both final states containing the spin-triplet ϒð1S; 2S; 3SÞ and spin-singlet h b ð1P; 2PÞ can be naturally understood [24].…”

The hidden-charm pentaquark and tetraquark states

“…The counterparts of Z c and their decay modes were studied in Ref. [499] using the effective Lagrangian based on the heavy quark symmetry.…”