Related papers: The $Y(4230)$ as a $D_1 \bar{D}$ molecule
The Belle Collaboration recently discovered the first manifestly exotic meson: Z^+(4430), which decays into psi' pi^+ and therefore has quark content c c-bar u d-bar. The proximity of its mass to the D_1 D-bar^* threshold has motivated the…
The $P_c(4380)$ and $P_c(4450)$ states observed recently by LHCb experiment were proposed to be either $\bar{D} \Sigma_c^*$ or $\bar{D}^* \Sigma_c$ S-wave bound states of spin parity $J^P={\frac32}^-$. We analyze the decay behaviors of such…
Cross sections for the process $e^{+} e^{-} \to K_{S}^{0} K_{S}^{0} J/\psi$ at center-of-mass energies from $4.128$ to $4.950$ GeV are measured using data samples with a total integrated luminosity of 21.2 fb$^{-1}$ collected by the BESIII…
Based on $\eta$-$\eta'$ mixing analysis, we propose a novel method to extract the physical solutions for the hadronic properties of the $Y(4230)$ resonance from the experimental data. Experimentally, multiple solutions have been reported in…
In this work we study the properties of hadronic molecules in the heavy-quark sector. These have become increasingly important since from the beginning of this century a large number of states have been measured that for different reasons…
In the present work, we estimate the decays of the $X(5568)$ and $X(5616)$ in a $B \bar{K}$ and a $B^\ast \bar{K}$ $S$-wave hadronic molecule scenarios, respectively, which may corresponding to the structure observed by D0 Collaboration.…
The new particle $D^{*}_{s1}(2700)^{+}$ has stimulated many attentions. There are different assignments of its inherent properties. It may be a $2^3S_1$, $1^3D_1$ or the mixture of $2^3S_1-1^3D_1$ $c\bar s$ $1^-$ state. By considering its…
Whether the $Y(4260)$ can couple to open charm channels has been a crucial issue for understanding its nature. The available experimental data suggest that the cross section line shapes of exclusive processes in $e^+e^-$ annihilations have…
We study $D_s^+ D_s^-$ and $D \bar D$ states assuming that they are hadronic molecules with $J^{PC}=0^{++}$ quantum number. We use two-point QCD sum rule formalism and extract the mass and decay constant values of these states. We take into…
Recently, a new structure $Y(4626)$ was reported by the Belle Colloboration in the process $e^+e^-\to D_s^+D_{s1}(2536)^-$. In this work, we propose an assignment of the $Y(4626)$ as a ${D}^*_s\bar{D}_{s1}(2536)$ molecular state, which…
Recent BESIII data indicate a significant rate of the process $e^+e^- \to h_c \pi^+ \pi^-$ at the Y(4260) and Y(4360) resonances, implying a substantial breaking of the heavy quark spin symmetry. We consider these resonances within the…
The interpretation of Y(4140) as a $D^{*}_s\bar{D}^{*}_s$ molecule is studied dynamically in the one boson exchange approach, where $\sigma$, $\eta$ and $\phi$ exchange are included. Ten allowed $D^{*}_s\bar{D}^{*}_s$ states with low spin…
Since its first observation in 2005, the vector charmonium $Y(4260)$ has turned out to be one of the prime candidates for an exotic state in the charmonium spectrum. It was recently proposed that the $Y(4260)$ should have a prominent…
Assuming that $D_{s0}^{*}(2317)$ is a $DK$ molecular state with a binding energy of 45 MeV, we investigate the existence of four-hadron molecules, $DDKK$ and $D\Bar{D}K\Bar{K}$, with the Gaussian expansion method. Their binding energies are…
We discuss a possible interpretation of the open charm mesons $D_{s0}^*(2317)$, $D_{s1}(2460)$ and the hidden charm mesons X(3872), Y(3940) and Y(4140) as hadron molecules. Using a phenomenological Lagrangian approach we review the strong…
In this work, we first propose the isovector $nD^{*}_0(2400)^0$ molecular state to explain the enhancement structure around 3250 MeV ($X_c(3250)^0$) in the $\Sigma_c^{++}\pi^-\pi^-$ invariant mass spectrum newly observed by the BaBar…
Pion exchange in S-wave between hadrons that are themselves in a relative S-wave is shown to shift energies by hundreds of MeV, leading to deeply bound quasi-molecular states. In the case of charmed mesons $D^*,D_1$ a spectroscopy arises…
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…
In this presentation the notion of hadronic molecules is reviewed and it is argued that some of the enigmatic single and double heavy mesons, namely the lowest lying positive parity open charm states, the $T_{cc}(3875)^+$ and the…
We study the vector-vector interaction within the framework of the hidden gauge formalism for the sector with quantum numbers charm C=0 and strangeness S=0 in the region around 4000 MeV. We get five poles, three of which could be identified…