Related papers: $X(3872)$ electromagnetic decay in a coupled-chann…
We systematically construct all the tetraquark currents of $J^{PC} = 1^{++}$ with the quark configurations $[cq][\bar c \bar q]$, $[\bar c q][\bar q c]$, and $[\bar c c][\bar q q]$ ($q=u/d$). Their relations are derived using the Fierz…
Radiative E1 decay widths of $\rm X(3872)$ are calculated through the relativistic Salpeter method, with the assumption that $\rm X(3872)$ is the $\chi_{c1}$(2P) state, which is the radial excited state of $\chi_{c1}$(1P). We firstly…
The chromomagnetic interaction, with proper account for flavour-symmetry breaking, is shown to explain the mass and coupling properties of the X(3872) resonance as a $J^{PC}$ = 1$^{++}$ state consisting of a heavy quark-antiquark pair and a…
Assuming $X(6900)$ is a tetraquark state, the decay width of $X(6900)\to 2J/\psi$ is calculated in a covariant quark model, with the diquark-antidiquark $[cc][\bar{c}\bar{c}]$ picture. Two possible structures, vector-vector and…
Analyses of the J/{\psi} {\pi}+ {\pi}- decay channel of the X(3872) resonance by the CDF, Belle, and LHCb collaborations have established its J^{PC} quantum numbers as 1^{++}. An analysis of the \pi+ \pi- \pi 0 invariant mass distribution…
Hidden-charm strong decays of the spin-2 partner $X_2(4014)$ of the charmonium-like state $X(3872)$ have been studied in the framework of the covariant confined quark model. The exotic state $X_2$ has been interpreted as a four-quark state…
Starting from the hypothesis that the X(3872) is a $D\bar D^*$ molecule, we discuss the radiative decays of the X(3872) into $\gamma J/\psi$ and $\gamma\psi'$ from an effective field theory point of view. We show that radiative decays are…
Recently, we have shown that the $X(3872)$ state can be naturally generated as a bound state by incorporating the hadron interactions into the Godfrey-Isgur quark model using the Friedrichs-like model combined with the QPC model, in which…
We report the observation of the X(3872) in the J/psi pi+pi- channel, with J/psi decaying to mu+mu- in p-p(bar) collisions at sqrt(s) = 1.96 TeV. Using approximately 230 pb^-1 of data collected with the Run II D0 detector, we observe 522…
If the quantum numbers of the X(3872) are J^{PC}=1^{++}, the measurement of its mass implies that it is either a loosely-bound hadronic molecule whose constituents are a superposition of the charm mesons pairs D^{*0} Dbar^0 and D^0…
We systematically investigate the mass spectrum and two-body open-charm strong decays of charmonium states in a coupled-channel model where the $^3P_0$ quark-antiquark pair creation mechanism is employed. The results of masses, mass shifts,…
A solvable coordinate-space model is employed to study the $c\bar{c}$ component of the X(3872) wave function, by coupling a confined $^3P_1$ $c\bar{c}$ state to the almost unbound $S$-wave $D^0\bar{D}^{*0}$ channel via the $^3P_0$…
The X(3872) has non-charmonium-like properties, such as decay processes that seem to violate isospin, and a mass that lies unexpectedly close to the neutral-D-plus-neutral-D-excited-state threshold. An EFT that includes both charmonium-like…
It is proposed that the newly discovered X(3872) is a $J^{PC} = 1^{++}$ $D^0\bar D^{0*}$ hadronic resonance stabilized by admixtures of $\omega J/\psi$ and $\rho J/\psi$. A specific model of the state is constructed and tests of its…
We study the X(3872)-->D^0 \bar D^0 \pi^0 decay within a D \bar D^* molecular picture for the X(3872) state. This decay mode is more sensitive to the long-distance structure of the X(3872) resonance than its J/\psi\pi\pi and J/\psi3\pi…
We present an analysis of angular distributions and correlations of the X(3872) particle in the exclusive decay mode X(3872)->J/psi pi+ pi- with J/psi->mu+ mu-. We use 780 pb -1 of data from ppbar collisions at sqrt{s} = 1.96 TeV collected…
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…
The decay rates and spectroscopy of the $Q \bar Q$ $(Q \in c, b)$ mesons are computed in non-relativistic phenomenological quark antiquark potential of the type $V(r)=-\frac{\alpha_c}{r}+A r^{\nu}$, (CPP$_{\nu}$) with different choices…
Contrary to almost standard opinion that the X(3872) resonance is the D^{*0}\bar D^0+c.c. molecule or the qc\bar q\bar c four-quark state, we discuss the scenario where the X(3872)resonance is the c\bar c = \chi_{c1}(2P) charmonium which…
We present a renormalization-group analysis of the $X(3872)$ radiative decays into $J/ \psi \gamma$ and $\psi(2S) \gamma$. We assume a $D\bar{D}^{*}$ molecule for the $X$ long-distance structure and parametrize its short-distance physics as…