Related papers: The 2^-+ assignment for the X(3872)

We further explore the consequences of treating the X(3872) meson as a tetraquark bound state by analyzing its one-photon decay X => \gamma + J/psi in the framework of our approach developed in previous papers which incorporates quark…

We have searched for exclusive production of exotic charmonia in the reaction $\mu^+~N \rightarrow \mu^+ (J\!/\!\psi\pi^+\pi^-)\pi^{\pm}~N'$ using COMPASS data collected with incoming muons of 160 GeV/$c$ and 200 GeV/$c$ momentum. In the…

We study the radiative decay of $X(3872)$ based on the assumption that $X(3872)$ is regarded as a $c\overline{c}$ charmonium with quantum number $J^{PC}=1^{++}$ ($J,\,P,\,C$ represent the spin, parity and charge conjugation, respectively).…

We present measurements of the decays B+ -> X(3872) K+ and B0 -> X(3872) K0 with X(3872) -> Jpsi pi+ pi-. The data sample used, collected with the BABAR detector at the PEP-II e+e- asymmetric-energy storage ring, corresponds to 455 x 10^6…

We analyze various possible interpretations of the narrow state $D_{sJ}^+(2632)$ observed by SELEX Collaboration recently, which lies above threshold and has abnormal decay pattern. These interpretations include: (1) several versions of…

Recent results by BELLE and BaBar point to the existence of a second X particle decaying in D^0 D^0bar pi^0, a few MeV above the X(3872). We identify the two X states with the neutral particles predicted by the 4-quark model and show that…

We generalise the framework of Dyson-Schwinger and Bethe-Salpeter equations for four-quark states to accommodate the case of unequal quark masses. As a first application, we consider the quantum numbers $I(J^{PC})=0(1^{++})$ of the…

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…

We investigate the decays of $B^0 \to K^0 X(3872)$ and $B^+ \to K^+ X(3872)$ based on the picture where the $X(3872)$ resonance is strongly coupled to the $D\bar{D}^* + c.c.$ channel. In addition to the decay mechanism where the $X(3872)$…

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 spectral function of the axial-vector charmonium state $\chi_{c1}(2P)$ coupled to $DD^{\ast}$ mesons, by employing a quantum field theoretical approach: a pronounced enhancement close to the $D^{0}% D^{\ast0}$ threshold, to be…

We use QCD sum rules to test the nature of the meson X(3872), assumed to be a mixture between charmonium and exotic molecular [c\bar{q}][q\bar{c}] states with J^{PC}=1^{++}. We find that there is only a small range for the values of the…

In this talk, we review our recent work about the dynamical studies of $Z^+(4430)$ and X(3872). $Z^+(4430)$ can not be explained as a $D_1'D^*$ or $D_1D^*$ molecular state only considering one pion exchange potential without the cutoff,…

Decays of X(3872) and its partners as hidden-charm axial-vector tetra-quark mesons are studied. As the result, it is seen that the iso-triplet partners of X(3872) can be broad, and therefore, higher statistics would be needed to find them.

New data for X(3872) production in B decays provide a separation between X production and decay, sharpen several experimental puzzles and impose serious constraints on all models. Both charged and neutral B decays produce a narrow neutral…

We study in the framework of a constituent quark model the possible contributions of molecular structures to the XYZ charmonium like states. We analyze simultaneously the $c\bar{c}$ structures and the possible molecular components in a…

In this paper, we calculate mass and probability fractions of meson-meson components of $X(3872)$ in an unquenched quark model. Different from most of other unquenched quark models, the quark pairs creation operator from $^3P_0$ is modified…

We study the two-body decays of B^\pm mesons to K^\pm and a charmonium state, X_{c\bar c}, in a sample of 210.5 fb^{-1} of data from the BaBar experiment. We perform measurements of absolute branching fractions BR(B^\pm --> K^\pm X_{c\bar…

After constructing all the tetraquark interpolating currents with $J^{PC}=1^{-+}, 1^{--}, 1^{++}$ and $1^{+-}$ in a systematic way, we investigate the two-point correlation functions to extract the masses of the charmonium-like states with…

Radiative decays of X(3872) with $J^{PC}=1^{++}$ are studied in the coupled-channel approach, where the $c\bar c$ states are described by relativistic string Hamiltonian, while for the decay channels $DD^*$ a string breaking mechanism is…