Related papers: Exploring a $\Sigma_{c}\bar{D}$ state: with focus …
We investigate whether the newly observed narrow resonance $Z_{c}(4025)$ can be described as a $D^{*}\bar{D^{*}}$ molecular state with quantum numbers $J^{P}=1^{+}$. Using QCD sum rules, we consider contributions up to dimension six in the…
We have used QCD sum rules to study the newly observed charged state $Z_c(4025)$ as a hidden-charm $D^*\bar D^*$ molecular state with the quantum numbers $I^G(J^{P})=1^+(1^{+})$. Using a $D^*\bar D^*$ molecular interpolating current, we…
The new strange pentaquarks observed by LHCb are very likely hadronic molecules consisting of $\Xi_c \bar D$ and $\Xi_c \bar D^{*}.$ We discuss the experimental evidence supporting this conclusion, pointing out the similarities and…
By using QCD sum rules, the mass of the hidden charm tetraquark $[cu][\bar{c}\bar{d}]$ state with $I^{G} (J^{P}) = 1^+ (1^{+})$ (HCTV) is estimated, which presumably will turn out to be the newly observed charmonium-like resonance…
We show that the currently available data are consistent with $Y(4230)$ being a $D_1 \bar{D}$ hadronic molecule. By a simultaneous fit to data from $e^+ e^- \rightarrow D^0 D^{* -} \pi^+,\: J/\psi \pi^+ \pi^-,\: J/\psi K^+ K^-,\: h_c \pi^+…
QCD sum rules are used to study the mass spectrum of bottom-charm hybrid $\bar bGc$ systems. The correlation functions and the spectral densities are calculated up to dimension six condensates at leading order of $\alpha_s$ for several…
We investigate the observed pentaquark candidates $P_c(4312)$, $P_c(4440)$ and $P_c(4457)$ from the latest LHCb measurement, as well as four possible spin partners in the $\bar{D}^{(*)}\Sigma_c^*$ system predicted from the heavy quark spin…
We use QCD sum rules to study the recently observed meson $Z^+(4430)$, considered as a $D^*D_1$ molecule with $J^{P}=0^{-}$. We consider the contributions of condensates up to dimension eight and work at leading order in $\alpha_s$. We get…
The nature of the $P_{c}(4312)$, $P_c(4440)$ and $P_c(4457)$ pentaquarks is a fascinating theoretical question. Within the molecular picture their more usual interpretation is that of $I=\tfrac{1}{2}$ $\bar{D} \Sigma_c$ and $\bar{D}^*…
There may exist seven $\bar D^{(*)} \Sigma_c^{(*)}$ hadronic molecular states. We construct their corresponding interpolating currents, and calculate their masses and decay constants using QCD sum rules. Based on these results, we calculate…
Recently, LHCb collaboration reported the observation of two hidden-charmed resonances $P_c(4380)$ and $P_c(4450)$ consistent with hidden-charmed pentaquarks. We perform a dynamical investigation about the $\bar{D}\Sigma_c^*(2520)$ and…
New LHCb Collaboration results on pentaquarks with hidden charm [1] are discussed. These results fit nicely in the hadrocharmonium pentaquark scenario [2,3]. In the new data the old LHCb pentaquark $P_c(4450)$ splits into two states…
In this article, we study the $S\bar{S}$ type scalar tetraquark state $cq\bar{c}\bar{q}$ in details with the QCD sum rules by calculating the contributions of the vacuum condensates up to dimension-10 in the operator product expansion, and…
The recent experimental results of LHCb collaboration suggested the existence of pentaquark states with charmonium. To understand the structure of the states, a dynamical calculation of 5-quark systems with quantum numbers…
On March 26th, 2019, at the Rencontres de Moriond QCD conference, the LHCb Collaboration reported the observation of three new pentaquarks, namely $P_c(4312)$, $P_c(4440)$ and $P_c(4457)$, which are consistent with the loosely bound…
A narrow pentaquark state, $P_c(4312)^+$, decaying to $J/\psi p$ is discovered with a statistical significance of $7.3\sigma$ in a data sample of ${\Lambda_b^0\to J/\psi p K^-}$ decays which is an order of magnitude larger than that…
By using QCD Sum Rules, we found that the charged hidden charm tetraquark $[c u][\bar{c} \bar{d}]$ states with $ J^P = 1^-$ and $ 2^+$, which are possible quantum numbers of the newly observed charmonium-like resonance $Z_c(4025)$, have…
Based on a coupled-channel approach, we investigate the structures of four $P_c$ states through compositeness criteria. Toward a more precise description of the states, we have obtained refined fit results of the LHCb data on the $J/\psi p$…
Very recently, the LHCb Collaboration reported their new results about the pentaquarks at charm energy region. Based on the new experimental results, we recalculate the molecular states composed of a $\Sigma_c^{(*)}$ baryon and a…
In this contribution we study the nature of the new Pc$(4312)^+$ signal reported by LHCb collaboration in the $J/\psi\,p$ spectrum. We use $S$-matrix principles to perform a minimum-bias analysis of the data, focusing on the analytic…