Related papers: A QCD sum rule calculation for the Y(4140) narrow …

We use QCD sum rules to test the nature of the recently observed mesons Y(4260), Y(4350) and Y(4660), assumed to be exotic four-quark $(c\bar{c}q\bar{q})$ or $(c\bar{c}s\bar{s})$ states with $J^{PC}=1^{--}$. We work at leading order in…

In this article, we assume that there exists a scalar $D_s^\ast {\bar D}_s^\ast$ molecular state in the $J/\psi \phi$ invariant mass distribution, and study its mass using the QCD sum rules. The predictions depend heavily on the two…

Masses for the $(Q\bar{s})^{(*)}(\bar{Q}s)^{(*)}$ ($Q=c$ or $b$) molecular states are systematically computed in the framework of QCD sum rules. Technically, contributions of the operators up to dimension six are included in operator…

Using the QCD sum rules we test if the charmonium-like structure Y(4274), observed in the $J/\psi\phi$ invariant mass spectrum, can be described with a $D_s\bar{D}_{s0}(2317)+h.c.$ molecular current with $J^{PC}=0^{-+}$. We consider the…

Using the QCD sum rules we test if the charmonium-like structure Y(4260), observed in the $J/\psi\pi\pi$ invariant mass spectrum, can be described with a $J/\psi f_0(980)$ molecular current with $J^{PC}=1^{--}$. We consider the…

In this article, we assume that there exist scalar ${D}^\ast {\bar {D}}^\ast$, ${D}_s^\ast {\bar {D}}_s^\ast$, ${B}^\ast {\bar {B}}^\ast$ and ${B}_s^\ast {\bar {B}}_s^\ast$ molecular states, and study their masses using the QCD sum rules.…

In this article, we assume that the narrow structure X(4350) is a scalar $\bar{c}c-{D}_s^\ast {\bar {D}}_s^\ast$ mixing state, and study its mass using the QCD sum rules. The numerical result $M_X=(4.37\pm0.15)\,\rm{GeV}$ is in good…

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…

In this article, we assume that there exists a pseudoscalar $D_s{\bar D}_{s0}(2317)$ molecular state and study its mass with the molecule-type interpolating current in details using the QCD sum rules. The numerical result disfavors…

The BESIII collaboration has discovered a new state with hidden charm-strange. Its mass is intriguingly close to the $ D_s\bar{D}_{s1} $ threshold and does not have the properties of the charmonium states. Working with the QCD sum rules…

If the $X(3872)$ is described by the picture as a mixture of the charmonium and molecular $D^{\ast} D$ states; $Y(3940)$ as a mixture of the $\chi_{c0}$ and $D^\ast D^\ast$ states; and $X(4260)$ as a mixture of the tetra-quark and…

The QCD sum rule approach is used to analyze the nature of the rencently observed new resonance $X(4350)$, which is assumed to be a diquark-antidiquark state $[cs][\bar{c}\bar{s}]$ with $J^{PC}=1^{-+}$. The interpolating current…

In this thesis, the QCD sum rules approach has been used to study the nature of the following charmonium resonances: Y(3930), Y(4140), X(4350), Y(4260), Y(4360) and Y(4660). There is a strong evidence that these states have non-conventional…

We systematically investigate the mass spectra of $\{Q\bar{s}\}\{\bar{Q}^{(')}s\}$ molecular states in the framework of QCD sum rules. The interpolating currents representing the molecular states are proposed. Technically, contributions of…

Using the QCD sum rules we test if the new narrow structure, the X(4350) recently observed by the Belle Collaboration, can be described as a $J^{PC}=1^{-+}$ exotic $D_s^*D_{s0}^*$ molecular state. We consider the contributions of…

In this article, we assign the $Y(4390)$ and $Y(4220)$ to be the vector molecular states $D\bar{D}_1(2420)$ and $D^*\bar{D}_0^*(2400)$, respectively, and study their masses and pole residues with the QCD sum rules in details. The present…

In this work, we chose three molecular and three diquark-antidiquark currents with the quark content $c\bar{c}s\bar{s}$ and $J^{PC}=0^{++},1^{++},2^{++}$, and estimated the masses and the meson coupling constants of the ground states…

In this article, we take the vector charmonium-like state Y(4660) as a $\psi'f_0(980)$ bound state (irrespective of the hadro-charmonium and the molecular state) tentatively, study its mass using the QCD sum rules, the numerical value…

We use QCD sum rules to study the possible existence of $QQ-\bar{u}\bar{d}$ mesons, assumed to be a state with $J^{P}=1^{+}$. For definiteness, we work with a current with an axial heavy diquark and a scalar light antidiquark, at leading…

This work uses the QCD Sum Rules to study the masses of the $D_s \bar{D}_s^*$ and $D_s^* \bar{D}_s^*$ molecular states with quantum numbers $J^{PC} = 1^{+-}$. Interpolating currents with definite C-parity are employed, and the contributions…