相关论文: $Z_c(4430)$ and $Z_c(4200)$ as triangle singularit…
Charmonium is a bound state of a charmed quark and a charmed antiquark, and a charmoniumlike state is a resonant structure that contains at least a charmed quark-antiquark pair but has properties that are incompatible with a conventional…
Several charged charmonium-like hadrons called $Z_c$ have been recently discovered by different experiments. In contrast to conventional hadrons these contain at least two valence quarks and antiquarks ($\bar{c}c\bar{d}u$). We perform a…
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…
We systematically investigate the mass spectrum and two-body open-charm strong decays of charmonium states in a coupled-channel model where the $^3P_0$ quark-antiquark pair creation mechanism is employed. The results of masses, mass shifts,…
Recent LHCb data for $B^-\to J/\psi\Lambda\bar{p}$ show a clear peak structure at the $\Xi_c\bar{D}$ threshold in the $J/\psi\Lambda$ invariant mass ($M_{J/\psi\Lambda}$) distribution. The LHCb's amplitude analysis identified the peak with…
We present a concise review of the vector charmonium state $\psi(4230)$, which was originally labelled as $Y(4260)$ in the literature. As one of the earliest candidates for a QCD exotic states, its interpretation has initiated various ideas…
In this article, we tentatively assign the $Z_c(4600)$ to be the $[dc]_P[\bar{u}\bar{c}]_A-[dc]_A[\bar{u}\bar{c}]_P$ type vector tetraquark state and study its two-body strong decays with the QCD sum rules based on solid quark-hadron…
The charm quark density-density correlation is calculated for $1S$ and $1P$ conventional charmonia and $J^{PC}=1^{-+},0^{+-}$ charmoniumlike states from lattice QCD and are interpreted as spatial wave functions of these states with some…
Recently the LHCb experiment found evidence for the existence of two exotic resonances consisting of $c\bar{c}uud$ quarks. Among the possible interpretations is the hadro-charmonium model, in which charmonium is bound "within" a light…
Based on our previous QCD sum rule studies on hidden-charm pentaquark states, we discuss possible interpretations of the $P_c(4312)$, $P_c(4440)$, and $P_c(4457)$, which were recently observed by LHCb. Our results suggest that the…
Hadrons and their distributions are the most direct observables in experiment, which would shed light on the non-perturbative mystery of quantum chromodynamics (QCD). As the result, any new hadron will challenge our current knowlege on the…
Using 586 pb$^{-1}$ of $e^+e^-$ annihilation data taken with the CLEO-c detector at $\sqrt{s}=4170$ MeV, the peak of the charmonium resonance $\psi(4160)$, we analyze the decay $\psi(4160)\to \pi^+\pi^- J/\psi$, and report observation of…
The newly observed $X, Y, Z$ exotic states are definitely not in the standard $Q\bar Q'$ structures, thus their existence composes a challenge to our understanding on the fundamental principles of hadron physics. Therefore the studies on…
The newly reported exotic signal $Z_c(4100)$ by the LHCb Collaboration in the invariant mass spectrum of $\eta_c\pi^-$ in $B^0\to \eta_c K^+ \pi^-$ has been a new experimental evidence for an exotic meson containing four constituent quarks.…
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…
The recent confirmation of the charged charmonium like resonance Z(4430) by the LHCb experiment strongly suggests the existence of QCD multi quarks bound states. Some preliminary results about hypothetical flavored tetraquark mesons are…
In the past decade many charmonium-like states were observed experimentally. Especially those charged charmonium-like $Z_c$ states and bottomonium-like $Z_b$ states can not be accommodated within the naive quark model. These charged $Z_c$…
Many newly discovered mesons behave like $\ccbar$ charmonium states in that they preferentially decay into final states that contain a $c$- and a $\bar{c}$-quark, but do not fit expectations for any of the unfilled levels of the…
The LHCb collaboration has detected a new hidden-charm pentaquark with the quantum numbers of a $\Lambda$ baryon: the $P_{\psi s}^{\Lambda}(4338)$. This pentaquark will be interpreted as a $\bar{D}_s \Lambda_c$-$\bar{D} \Xi_c$ resonance…
Recent experiments at the LHCb detector have once again raised the possibility that quark bags may exist containing more than three quarks. Specifically the LHCb collaboration points to evidence for hadronic resonances decaying into…