Four-quark structure of Zc(3900), Z(4430) and Xb(5568) states

Abstract

We examine the four-quark structure of the recently discovered charged $Z_c(3900)$, $Z(4430)$, and $X_b(5568)$ states. We calculate the widths of the strong decays $Z_c^{+}\to J/\psi {\pi }^{+}$ (${\eta }_c{\rho }^{+}$, ${\bar{D}}^0{D}^{\ast +}$, ${\bar{D}}^{\ast 0}{D}^{+}$), $Z(4430{)}^{+}\to J/\psi {\pi }^{+}$ ($\psi (2s){\pi }^{+}$), and $X_b^{+}\to B_s{\pi }^{+}$ within a covariant quark model previously developed by us. We find that the tetraquark-type current widely used in the literature for the $Z_c(3900)$ leads to a significant suppression of the $\bar{D}{D}^{\ast }$ and ${\bar{D}}^{\ast }D$ modes. Contrary to this a molecular-type current provides an enhancement by a factor of 6-7 for the $\bar{D}{D}^{\ast }$ modes compared with the $Z_c^{+}\to J/\psi {\pi }^{+}$, ${\eta }_c{\rho }^{+}$ modes in agreement with recent experimental data from the BESIII Collaboration. In case of the $Z(4430)$ state we test a sensitivity of the ratio $R_Z$ of the $Z(4430{)}^{+}\to \psi (2s){\pi }^{+}$ and $Z(4430{)}^{+}\to J/\psi {\pi }^{+}$ decay rates to a choice of the size parameter ${\Lambda }_{Z(4430)}$ of the $Z(4430)$. Using upper constraint for the sum of these two modes deduced from the LHCb Collaboration data we find that $R_Z$ varies from 4.64 to 4.08 when ${\Lambda }_{Z(4430)}$ changes from 2.2 to 3.2 GeV. Also we make the prediction for the $Z(4430{)}^{+}\to D^{\ast +}{\bar{D}}^{\ast 0}$ decay rate.

14 pages

References in corpus (19)

• Observation of a resonance-like structure in the pi^+- psi' mass distribution in exclusive B-->K pi^+- psi' decays
• Observation of the resonant character of the $Z(4430{)}^{-}$ state
• Exclusive semileptonic and nonleptonic decays of the Bc meson
• Strong and radiative decays of the Ds0*(2317) meson in the DK-molecule picture
• Observation of a new charged charmoniumlike state in B -> J/psi K pi decays
• Hadronic molecule structure of the Y(3940) and Y(4140)
• Estimate for the X(3872) to gamma J/psi decay width
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• D* K molecular structure of the Ds1(2460) meson
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• Radiative decay of Lambdac(2940)+ in a hadronic molecule picture
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• Ds0*(2317) and Ds1(2460) mesons in two-body B-meson decays
• Molecular structure of the Bs0*(5725) and Bs1(5778) bottom-strange mesons
• Hidden-charm and radiative decays of the Z(4430) as a hadronic D_1 \bar{D^\ast} bound state
• Radiative and dilepton decays of the hadronic molecule Zc(3900)+
• Two-photon decay of heavy hadron molecules
• Weak decays of heavy hadron molecules involving the f0(980)
• XYZ physics at BESIII experiment

Cited by in corpus (19)

• Pentaquark and Tetraquark states
• Hadronic molecules in B decays
• Open charm and bottom tetraquarks in an extended relativized quark model
• Treating $Z_c(3900)$ and $Z(4430)$ as the ground-state and first radially excited tetraquarks
• Study of charmonium-like and fully-charm tetraquark spectroscopy
• Triply heavy tetraquark states with the $QQ\bar{Q}\bar{q}$ configuration
• Open-flavor charmed/bottom $sq\bar{q}\bar{Q}$ and $qq\bar{q}\bar{Q}$ tetraquark states
• Magnetic and quadrupole moments of the $Z_c(3900)$
• $Z_b(10610)$ and $Z_b^{\prime }(10650)$ decays in a covariant quark model
• The decays of the fully open flavor state $T_{c\bar{s}0}^0$ in a $D^{\ast }{K}^{\ast }$ molecule scenario
• Tetraquarks in holographic QCD
• Test of the multiquark structure of $a_1(1420)$ in strong two-body decays
• Radiative decays $D^*_{(s)}\to D_{(s)}γ$ in covariant confined quark model
• Universal non-resonant explanation to charmoniumlike structures $Z_c(3885)$ and $Z_c(4025)$
• Modifications on parameters of $Z(4430)$ in a dense medium
• $Z_c$ and $Z_{cs}$ systems with operator mixing at NLO in QCD sum rules
• Probing the ATOMKI X17 vector boson using Dalitz decays $V\to P{e}^{+}{e}^{-}$
• Investigating the internal structure of $X(6900)$ in the $2J/\psi$ decay channel
• Radiative transitions of charmonium states in the covariant confined quark model