Related papers: Estimate for the X(3872) to gamma J/psi decay widt…

By describing the $X(3872)$ using the extended Friedrichs scheme, in which $D\bar D^*$ is the dominant component, we calculate the decay rates of the $X(3872)$ to $\pi^0$ and a $P$-wave charmonium $\chi_{cJ}$ state with $J=0,1$, or $2$, and…

It has been proposed that the recently discovered archetypical "exotic" meson, X(3872), with M(X(3872))=3871.68+-0.17 MeV/c^2, and an extremely narrow width, Gamma(X(3872))<1.2 MeV, is a hadronic molecule of bound D^0 and D^*0 mesons. If…

We investigate heavy quark symmetries for heavy meson hadronic molecules, and explore the consequences of assuming the X(3872) and $Z_b(10610)$ as an isoscalar $D\bar D^*$ and an isovector $B\bar B^*$ hadronic molecules, respectively. The…

We analyze the recent data from the BESIII collaboration on the $X(3872)$ state in the $J/\psi\pi^+\pi^-$ and $D^0\bar{D}^0\pi^0$ decay channels. The quantum number and mass of the $X(3872)$ state allow us to exploit the universal feature…

We present an estimate of the partial width of X(3872) into p p-bar under the assumption that it is a weakly-bound hadronic molecule whose constituents are a superposition of the charm mesons D^{*0} D-bar^0 and D^{0} D-bar^{*0}. The p p-bar…

We use QCD sum rules to calculate the width of the radiative decay 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 in a small range for…

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 $X(3872)$…

It is pointed out that the internal structure of the narrow resonance X(3872) at the D^0 {\bar D}^{*0} threshold can be studied in some detail by measuring the rate and the spectra in the decays X(3872) \to D^0 {\bar D}^0 \pi^0 and X(3872)…

We re-examine the re-scattering mechanism for the X(3872), as a candidate for the 2P charmonium state $\chi_{c1}(2P)$, decaying to $J/\psi\rho(\omega)$ through exchanging $D^{(*)}$ mesons between intermediate states $D(\bar{D})$ and…

Because of the controversial X(3872) meson's very close proximity to the $D^0\bar{D}^{*0}$ threshold, this charmonium-like resonance is often considered a meson-meson molecule. However, a molecular wave function must be essentially of a…

It is pointed out that in the decays $X(3872) \to D {\bar D} \gamma$ the possible `molecular' component of the X(3872) should give rise essentially only to a $D^0 {\bar D}^0 \gamma$ final state with a predictable spectrum, and should yield…

We present results from a study of X(3872) --> pi+pi- J/psi decays produced via exclusive B--> K X(3872) decays. We determine the mass to be M_X(3872)= (3871.84\pm 0.27 (stat)\pm 0.19 (syst)) MeV, a 90% CL upper limit on the natural width…

It has been generally expected that the $X(3872)$ has a spin-2 partner, $X_2$, with quantum numbers $J^{PC}=2^{++}$. In the hadronic molecular model, its mass was predicted to be below the $D^*\bar D^*$ threshold, and the new structure…

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 report evidence for the decay modes X(3872) --> gamma J/psi and X(3872)--> pi+pi-pi0 J/psip. In the latter, the pi+pi-pi0 invariant mass distribution has a strong peak between 750 MeV and the kinematic limit of 775 MeV, suggesting that…

The decays of the X(3872) to P-wave quarkonia are calculated under the assumption that it is a shallow bound state of neutral charmed mesons. The X(3872) is described using an effective theory of nonrelativistic D mesons and pions (X-EFT).…

Enfant terrible of charmonium spectroscopy, the resonance $X(3872)$, generated a stream of interpretations and ushered in a new exotic $XYZ$ spectroscopy. In th meantime, many (if not all) characteristics of $X(3872)$ are rather ambiguous.…

Heavy hadron chiral perturbation theory (HHchiPT) and XEFT are applied to the decays X(3872) -> psi(2S) + gamma and psi(4040) -> X(3872) + gamma under the assumption that the X(3872) is a molecular bound state of neutral charm mesons. In…

We discuss the possibility that the X(3872) can be a $D\bar{D}^*$ molecular bound state in the Bethe-Salpeter equation approach in the ladder and instantaneous approximations. We show that the $D\bar{D}^*$ bound state with quantum numbers…

Radiative decays X --> psi(1S) + gamma and X --> psi(2S) + gamma might be expected to have a ratio of branching fractions following the phase space volumes ratio. However data suggest the opposite, indicating a value for R=B(X --> psi^prime…