Strange molecular partners of the $Z_c(3900)$ and $Z_c(4020)$

Abstract

Quantum Chromodynamics presents a series of exact and approximate symmetries which can be exploited to predict new hadrons from previously known ones. The $Z_c(3900)$ and $Z_c(4020)$ resonances, which have been theorized to be isovector $D^{\ast }\bar{D}$ and $D^{\ast }{\bar{D}}^{\ast }$ molecules [$I^G(J^{PC})=1^{-}(1^{+-})$], are no exception. Here we argue that from SU(3)-flavor symmetry, we should expect the existence of strange partners of the $Z_c$'s with hadronic molecular configurations $D^{\ast }{\bar{D}}_s$-$D{\bar{D}}_s^{\ast }$ and $D^{\ast }{\bar{D}}_s^{\ast }$ (or, equivalently, quark content $c\bar{c}s\bar{q}$, with $q=u,d$). The quantum numbers of these $Z_{cs}$ and $Z_{cs}^{\ast }$ resonances would be $I(J^P)$ = $\frac{1}{2}(1^{+})$. The predicted masses of these partners depend on the details of the theoretical scheme used, but they should be around the $D^{\ast }{\bar{D}}_s$-$D{\bar{D}}_s^{\ast }$ and $D^{\ast }{\bar{D}}_s^{\ast }$ thresholds, respectively. Moreover, any of these states could be either a virtual pole or a resonance. We show that, together with a possible triangle singularity contribution, such a picture nicely agrees with the very recent BESIII data of the $e^{+}{e}^{-}\to K^{+}(D_s^{-}{D}^{\ast 0}+D_s^{\ast -}{D}^0)$.

8 pages, 5 figures; note added commenting on the Zcs structures reported recently by LHCb

References in corpus (4)

• Observation of a near-threshold structure in the $K^{+}$ recoil-mass spectra in $e^{+}{e}^{-}\to K^{+}(D_s^{-}{D}^{\ast 0}+D_s^{\ast -}{D}^0)$
• Effect of charmed meson loops on charmonium transitions
• Explaining the Many Threshold Structures in the Heavy-Quark Hadron Spectrum
• Observation of e+e- to K+K-J/psi via Initial State Radiation at Belle

Cited by in corpus (46)

• An updated review of the new hadron states
• Chiral perturbation theory for heavy hadrons and chiral effective field theory for heavy hadronic molecules
• STCF Conceptual Design Report: Volume 1 -- Physics & Detector
• The $P_{cs}(4459)$ pentaquark from a combined effective field theory and phenomenological perspective
• Hadronic molecules in B decays
• Establishing the heavy quark spin and light flavor molecular multiplets of the $X(3872)$, $Z_c(3900)$ and $X(3960)$
• Exotic ${\bar{D}}_s^{(\ast )}{D}^{(\ast )}$ molecular states and $sc\bar{q}\bar{c}$ tetraquark states with $J^P=0^{+},1^{+},2^{+}$
• Predicting the ${\bar{D}}_s^{(\ast )}{D}_s^{(\ast )}$ bound states as the partners of $X(3872)$
• Implications of the $Z_{cs}(3985)$ and $Z_{cs}(4000)$ as two different states
• A combined analysis of the $Z_c(3900)$ and the $Z_{cs}(3985)$ exotic states
• Axial meson exchange and the $Z_c(3900)$ and $Z_{cs}(3985)$ resonances as heavy hadron molecules
• A unified description of the hidden-charm tetraquark states $Z_{cs}(3985)$, $Z_c(3900)$ and $X(4020)$
• Hidden-charm tetraquarks with strangeness in the chiral quark model
• Heavy Flavour Physics and CP Violation at LHCb: a Ten-Year Review
• Interpretations of the new LHCb $P_c(4337{)}^{+}$ pentaquark state
• Is $Z_{cs}(3982)$ a molecular partner of $Z_c(3900)$ and $Z_c(4020)$ states?
• Heavy-hadron molecular spectrum from light-meson exchange saturation
• Observation of a vector charmoniumlike state at 4.7 $\mathrm{GeV}/c^2$ and search for $Z_{cs}$ in $e^{+}{e}^{-}\to K^{+}{K}^{-}J/\psi$
• Heavy- and light-flavor symmetry partners of the $T_{cc}^{+}(3875)$, the $X(3872)$ and the $X(3960)$ from light-meson exchange saturation
• ${\bar{D}}_s^{(\ast )}{D}^{(\ast )}$ molecular state with $J^P=1^{+}$
• Evidence for a neutral near-threshold structure in the $K_{\mathrm{S}}^0$ recoil-mass spectra in $e^{+}{e}^{-}\to K_{\mathrm{S}}^0{D}_s^{+}{D}^{\ast -}$ and $e^{+}{e}^{-}\to K_{\mathrm{S}}^0{D}_s^{\ast +}{D}^{-}$
• Configuration mixing in strange tetraquarks $Z_{cs}$
• Magnetic dipole moments of the $Z_c(4020{)}^{+}$, $Z_c(4200{)}^{+}$, $Z_{cs}(4000{)}^{+}$ and $Z_{cs}(4220{)}^{+}$ states in light-cone QCD
• Strange hidden-charm tetraquarks in constituent quark models
• Predicting isovector charmonium-like states from X(3872) properties
• Threshold effects as the origin of $Z_{cs}(4000)$, $Z_{cs}(4220)$ and $X(4700)$ observed in $B^{+}\to J/\psi \varphi K^{+}$
• Precise determination of the pole position of the exotic $Z_c(3900)$
• Study on $Z_{cs}$ and excited $B_s^0$ states in the chiral quark model
• Semi-inclusive lepto-production of hidden-charm exotic hadrons
• Production of $Z_{cs}$ in $B$ and $B_s$ decay
• $Z_{cs}$ states from the $D_s^{\ast }{\bar{D}}^{\ast }$ and $J/\psi K^{\ast }$ coupled channels: Signal in $B^{+}\to J/\psi \varphi K^{+}$ decay
• Photo- and electro-production of narrow exotic states: from light quarks to charm and up to bottom
• The decay widths of the $Z_{cs}(3985/4000)$ based on rigorous quark-hadron duality
• Semi-inclusive electroproduction of hidden-charm and double-charm hadronic molecules
• $Z_{cs}(3985)$ in next-to-leading-order chiral effective field theory -- the first truncation uncertainty analysis
• Molecular $P_{\psi }$ pentaquarks from light-meson exchange saturation
• $X$ and $Z_{cs}$ in $B^{+}\to J/\psi \varphi K^{+}$ as $s$-wave threshold cusps and alternative spin-parity assignments to $X(4274)$ and $X(4500)$
• Role of the short-range dynamics in the formation of $D^{(\ast )}{\bar{D}}^{(\ast )}/B^{(\ast )}{\bar{B}}^{(\ast )}$ hadronic molecules
• Search for hidden-charm tetraquark with strangeness in $e^{+}{e}^{-}\to K^{+}{D}_s^{\ast -}{D}^{\ast 0}+c.c.$
• Hadronic medium effects on $Z_{cs}(3985{)}^{-}$ production in heavy-ion collisions
• $Z_c$ and $Z_{cs}$ systems with operator mixing at NLO in QCD sum rules
• The $Z_{cs}$ states and the mixture of hadronic molecule and diquark-anti-diquark components within effective field theory
• Spectrum of Hidden-Charm, Open-Strange Exotics in the Dynamical Diquark Model
• Hunting for the heavy quark spin symmetry partner of $Z_{cs}$
• Exotic hadrons associated with $b$-quark
• Decoding the near-threshold $X_{0,1}(4140)$ and $X_1(4685)$ states via OZI-suppressed coupled-channel scattering