Related papers: Understanding close-lying exotic charmonia states …
Observations of exotic structures in the $J/\psi p$ channel, that we refer to as pentaquark-charmonium states, in $\Lambda_b^0\to J/\psi K^- p$ decays are presented. The data sample corresponds to an integrated luminosity of 3/fb acquired…
New spectroscopy from the B factories, the advent of CLEO-c and the BES upgrade renewed the interest in charmonia. Among the new measurements, the state X(3872) has received special attention due to its unexpected properties. Its structure…
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…
We calculate the bound state properties of $J/\psi$ in a hot and dense QCD plasma using phenomenological potentials augmented by inputs from perturbative QCD. The temperature and density region of study will be relevant in future heavy ion…
In this article, we take the tensor currents $\bar{Q}(x)\sigma_{\mu\nu}Q(x)$ to interpolate the $P$-wave spin-singlet heavy quarkonium states $h_Q$, and study the masses and decay constants with the Borel sum rules and moments sum rules.…
A candidate triple strange pentaquark state, $P_{csss}$, is investigated through its strong decay channel $P_{csss} \rightarrow \Omega^-J/\psi $. To calculate the relevant strong coupling constants, two possible interpolating currents with…
We investigate the existence of bound states and resonances in the ${\phi NN, J/\psi NN, \eta_c NN}$ systems using HAL QCD interactions for ${\phi N, J/\psi N}$, and ${\eta_c N}$. We employ the Gaussian expansion method to solve the…
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 work, we adopt the diquark model, construct the diquark-diquark-antiquark type currents with the light quarks $uus$ in two octets, and study the $uusc\bar{c}$ pentaquark states in the framework of the QCD sum rules systematically.…
In the present work, the doubly-charm and doubly-bottom pentaquark molecular states $D^{(*)}\Sigma_c^{(*)}$ and $B^{(*)}\Sigma_b^{(*)}$ are studied via the QCD sum rules. Sixteen color singlet-singlet type currents with the definite…
The energies and widths of $DNN$ quasi-bound states with isospin I=1/2 are evaluated in two methods, the fixed center approximation to the Faddeev equation and the variational method approach to the effective one-channel Hamiltonian. The…
The in-medium masses of the lowest S-wave charmonium states (vector meson, $J/\psi$ and pseudoscalar meson, $\eta_c$) and P-wave charmonium states (scalar, $\chi_{c0}$ and axialvector $\chi_{c1}$) are investigated in magnetized nuclear…
In this work, we distinguish the isospin unambiguously to construct the diquark-diquark-antiquark type five-quark currents with the isospin $I=\frac{1}{2}$, and study the $uudc\bar{c}$ pentaquark states with the QCD sum rules systematically…
In the paper, we construct eight color singlet-singlet type five-quark currents with distinguished isospins to study the $\bar{D}\Xi^{\prime}$, $\bar{D}\Xi_c^{*}$, $\bar{D}^{*}\Xi_c^{\prime}$ and $\bar{D}^{*}\Xi_c^{*}$ molecular states with…
Exotic mesons with quantum numbers of a hybrid ($\bar{q} q g$) such as $J^{PC} = 1^{-+}$are shown to exist as narrow resonant states in the large $N_c$ limit of QCD. The width of these states is proportional to $1/N_c$. Possible…
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…
In this article, we take the point of view that the charmed mesons $D_{s0}(2317)$ and $D_{s1}(2460)$ with the spin-parity $0^+$ and $1^+$ respectively are the conventional $c\bar{s}$ states, and calculate the strong coupling constants…
In this article, we assume that there exist the pseudoscalar $D\bar{D}_{s0}^*(2317)$ and $D^*\bar{D}_{s1}^*(2460)$ molecular states $Z_{1,2}$ and construct the color singlet-singlet molecule-type interpolating currents to study their masses…
The experimental status concerning the two new narrow states with charm-strange content is reviewed. The states have masses of 2317 and 2460 MeV, widths less than 10 MeV, isospin consistent with zero, and spin-parities consistent with being…
Inspired by the states $T_{c\bar{s}0}^{a}(2900)^{0}$ and $T_{c\bar{s}0}^{a}(2900)^{++}$ reported by the LHCb Collaboration, we carry out a systematical investigation of the charm-strange pentaquark system using resonance group method in the…