Related papers: Could $Z_{c}(4025)$ be a $J^{P}=1^{+}$ $D^{*}\bar{…
We investigate the nature of the recently observed narrow resonance $Z_{c}(3900)$, which is assumed to be a $D^{*}\bar{D}$ molecular state with quantum numbers $I^{G}J^{P}=1^{+}1^{+}$. Using QCD sum rules, we consider contributions up to…
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…
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 have studied the loosely bound $D^*\bar{D}^*$ system. Our results indicate that the recently observed charged charmonium-like structure $Z_c(4025)$ can be an ideal $D^*\bar{D}^*$ molecular state. We have also investigated its pionic,…
We present a QCD sum rule analysis for the newly observed resonance $X_{c}(3250)$ by assuming it as a $D_{0}^{*}(2400)N$ molecular state. Technically, contributions of operators up to dimension 12 are included in the operator product…
Assuming the newly observed $Z_c(3900)$ to be a molecular state of $D\bar D^*(D^{*} \bar D)$, we calculate the partial widths of $Z_c(3900)\to J/\psi+\pi;\; \psi'+\pi;\; \eta_c+\rho$ and $D\bar D^*$ within the light front model (LFM).…
The recently observed narrow resonance $Z_{b}(10610)$ is examined with the assumptions both as a $B^{*}\bar{B}$ molecular state and a $[bd][\bar{b}\bar{u}]$ tetraquark state with quantum numbers $I^{G}J^{P}=1^{+}1^{+}$. Possible…
Stimulated by the observation of $\Lambda_c(2910)^+$ by the Belle Collaboration, the $S$-wave $qqq\bar{q}c~(q=u~\text{or}~d)$ pentaquark systems with $I$ = 0, $J^P$ = $\frac{1}{2}^-,~\frac{3}{2}^- and~\frac{5}{2}^-$ are investigated in the…
In the framework of QCD sum rules, we present an improved study of our previous work [Phys. Rev. D {\bf80}, 056004 (2009)] particularly on the $\bar{D}D^{*}$ molecular state to investigate that the possibility of the newly observed…
We present an analysis of the newly observed pentaquark $P_c(4312)^+$ to shed light on its quantum numbers. To do that, the QCD sum rule approach is used. The measured mass of this particle is close to $\Sigma_c^{++}\bar{D}^-$ threshold and…
Assuming the newly observed structure $Z_{b}(10610)$ as a bottomonium-like molecular state $B^{*}\bar{B}$, we calculate its mass in the framework of QCD sum rules. The numerical result is $10.54\pm0.22 GeV$ for $B^{*}\bar{B}$, which…
In this article, we study the $\bar{D}\Sigma_c$, $\bar{D}\Sigma_c^*$, $\bar{D}^{*}\Sigma_c$ and $\bar{D}^{*}\Sigma_c^*$ pentaquark molecular states with the QCD sum rules by carrying out the operator product expansion up to the vacuum…
In this work we study the $D^* \bar{D}^*$ current with QCD sum rules. We write the correlation function using the general current corresponding to the $D^* \bar{D}^*$ system and then use spin projectors to obtain the correlation function in…
At the invariant mass spectrum of $h_c\pi^\pm$ a new resonance $Z_c(4020)$ has been observed, however the previously confirmed $Z_c(3900)$ does not show up at this channel. In this paper we assume that $Z_c(3900)$ and $Z_c(4020)$ are…
Motivated by the LHCb's recent confirmation of $Z_1(4475)$ as the $J^P=1^+$ resonance, we investigate various exotic interpretations of $Z_1(4475)$, which may be an axial vector tetraquark state, the P-wave excitation of the S-wave $D_1…
We use QCD sum rules to study the recently observed resonance-like structures in the $\pi^+\chi_{c1}$ mass distribution, $Z_1^+(4050)$ and $Z_2^+(4250)$, considered as $D^{*+}\bar{D}^{*0}$ and $D_1^+\bar{D}^0+ D^+\bar{D}_1^0$ molecules with…
Within the framework of the local hidden gauge approach, we have studied the near-threshold interaction of the $D^* \bar{D}^*$ channel with quantum numbers $I(J^{PC}) = 0(0^{++})$, $0(2^{++})$, $1(0^{++})$, and $1(2^{++})$, respectively.…
The proximity of ${\rm Z}^+(4430)$ to the ${\rm D^{*}\bar{D}_1}$ threshold suggests that it may be a ${\rm D^{*}\bar{D}_1}$ molecular state. The ${\rm D^{*}\bar{D}_1}$ system has been studied dynamically from quark model, and state mixing…
In this article, we calculate the contributions of the vacuum condensates up to dimension-10 in the operator product expansion, and study the $J^{PC}=0^{++}$, $1^{+-}$, $2^{++}$ $D^*\bar{D}^*$, $D_s^*\bar{D}_s^*$, $B^*\bar{B}^*$,…
In this paper, we construct $\bar{D}^{(*)}_{s}D^{(*)}$-molecule-type interpolating currents $J_{(\pm)\mu}(x)$ with $J^{P}=1^{+}$, calculate the corresponding mass and magnetic moment using the QCD sum rule method and its extension in the…