Related papers: Pentaquarks and strange tetraquark mesons
LHCb recently announced the discovery of two exotic structures in the $J/\psi + p$ decay channel, which have been referred to as charmonium-pentaquark states. Resolving between the models and clarifying the nature of the discovered…
We perform a theoretical analysis of the $\Lambda_b \to J/\psi K^- p$ reaction from where a recent LHCb experiment extracts a $\Lambda(1405)$ contribution in the $K^- p$ spectrum close to threshold and two baryon states of hidden charm in…
The recent observation of two hidden-charm pentaquark states by LHCb collaborations prompted us to investigate the exotic states close to the $\bar{D}\Lambda_{\rm c}$, $\bar{D}^{\ast}\Lambda_{\rm c}$, $\bar{D}\Sigma_{\rm c}$,…
The decay behavior of an exotic state can be used to probe its internal structure. We note that the hidden-charm pentaquark states, $P_{\psi}^{N}(4312)$, $P_{\psi}^{N}(4440)$, and $P_{\psi}^{N}(4457)$, have only been observed in the $J/\psi…
Inspired by recent advances in the study of the $K^{(*)} \bar K^{(*)}$ molecular tetraquarks and the $H$-dibaryon, we focus on the spectroscopic properties of the $\bar K^{(*)} \bar K^{(*)}$ systems, which exhibit exotic flavor quantum…
We predict exotic doubly heavy--strange pentaquarks with minimal quark content $u\bar d sQQ'$ ($QQ'=cc,bc,bb$) within a coupled-channel unitary framework where the interaction is derived from an extension of the local hidden gauge approach…
In the framework of the color-magnetic interaction, we systematically investigate the mass splittings of the $QQ\bar{Q}\bar{q}$ tetraquark states and estimated their rough masses in this work. These systems include the explicitly exotic…
We study the three-body $\Lambda_b$ decays of $\Lambda_b\to J/\psi pM$ with $M=K^-$ and $\pi^-$. The two new states ${\cal P}_{c1}\equiv {\cal P}_c(4380)^+$ and ${\cal P}_{c2}\equiv {\cal P}_c(4450)^+$ observed recently as the resonances in…
The recent abundant observations of pentaquarks and tetraquarks by high-energy accelerator facilities indicate the realization of the conjecture by Gell-Mann and Zweig, and by De Rujula, Georgi and Glashow [1-3]. We construct a…
Since LEPS collaboration reported the first evidence of $\Theta^+$ pentaquark in early 2003, eleven other experimental groups have confirmed this exotic state while many other groups didn't see any signal. If this state is further…
If the exotic baryon $\Theta^+(1540)$ is a correlated $udud\bar{s}$ with $J^P = {1/2}^+$, then there should exist an exotic meson, $J^P = 1^-$ $\vartheta^+ (S=+2)$ $\to K^+K^0$ $\sim 1.6$GeV with width $O(10-100)$MeV. The $\pi_1(1400;1600)$…
The LHCb collaboration have recently updated their analysis of the resonant $J/\psi\, p$ mass spectrum in the decay $\Lambda_b^0 \to J/\psi\, p\, K^-$, making use of their combined Run~1 and Run~2 data. In the updated analysis, three narrow…
Recently, several pentaquark states $P_{css}$, with global flavor $\bar c c s s n$, have been predicted within a theoretical framework based on unitary coupled channels. We study theoretically the feasibility to observe the $P_{css}$ with…
This study investigates the properties of the $T_{\psi\psi}$ tetraquark candidates within a coupled-channels calculation of the $c\bar c- c\bar c$ system, specifically focusing on the $J^P=0^\pm$, $1^\pm$, and $2^\pm$ sectors. The analysis…
It is demonstrated that the candidate tetraquark states $Z_b(10610)$, $Z_b(10650)$, $Z_c(3900)$, and $Z_c(4025)$ are coupled channel cusp effects. The model explains in a natural way the masses and quantum numbers of the putative states and…
Very recently, the LHCb Collaboration reported a fully charmed tetraquark state $X(6900)$ in the invariant mass spectrum of $J/\psi$ pairs. If one $J/\psi$ meson is replaced with a fully charmed baryon, we obtain a fully charmed pentaquark…
The LHCb collaboration have recently updated their analysis of the resonant $J/\psi p$ mass spectrum in the decay $\Lambda_b^0 \to J/\psi p K^-$, making use of their combined Run 1 and Run 2 data. In the updated analysis, three narrow…
In this work, we study systematically the mass splittings of the $qq\bar{Q}\bar{Q}$ ($q=u$, $d$, $s$ and $Q=c$, $b$) tetraquark states with the color-magnetic interaction by considering color mixing effects and estimate roughly their…
Inspired by the LHCb's discovery of hidden-charm pentaquarks, the anticharmed strange pentaquarks $P_{\bar c s}$ in a favor of the hadronic molecule picture are investigated from the one-boson-exchange model. Similar to the hidden-charm…
We discuss the interpretation of the $J\!/\!\psi\,J\!/\!\psi$ peak recently seen by the LHCb collaboration at CERN, and take the opportunity to review the experimental and theoretical state of the art for exotic hadrons. It is stressed that…