Related papers: New Results on X(3872) from CDF
The $X(3872)$, whose mass coincides with the $D^0\bar D^{*0}$ threshold, is the most extended hadron object. Since its discovery in 2003, debates have never stopped regarding its internal structure. We propose a new object, the $X$ atom,…
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…
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…
We present recent studies of charmonium multiquark states. We use different interacting models and numerical methods to study deeply bound four-quark states and meson-meson molecules. No deeply bound four-quark states are found in our…
The discovery of the X(3872) in the 3\pi J/\psi mode is compelling evidence for its molecular nature. A successful prediction of this decay mode and other predictions are reviewed here.
We analyze how the renowned X(3872), a weakly bound state right below the $D \bar D^*$ threshold, should effectively be included in a hadronic representation of the QCD partition function. This can be decided by analyzing the $D \bar D^*$…
The X(3872) and Y(4260), both discovered in $\pi^+\pi^- J/\psi$ mode, are rather unusual: $X_c\equiv X(3872)$ is very narrow, while $Y_c \equiv Y(4260)$ has large $Y_c\to \pi^+\pi^-J/\psi$ width. Many models for their composition have been…
We have studied some possible four-quark and molecule contents of the X(3872) using double ratios of sum rules, which are more accurate than the usual simple ratios often used in the literature for getting the hadron masses. We found that…
The unusual properties of the X(3872) have led to speculation that it is a weakly bound state of mesons, chiefly $D^0\bar D^{0*}$. Tests of this hypothesis are investigated and it is proposed that measuring the $3\pi J/\psi$, $\gamma…
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…
Properties of X(3872) are studied by regarding it as a $DD^{\ast}$ hadronic molecule with $J^{PC} = 2^{-+}$ in the phenomenological Lagrangian approach. We find that our model with about 97.6% isospin zero component explains the existing…
We re-investigate the possibility of X(3872) as a $D\bar{D}^*$ molecule with $J^{PC}=1^{++}$ within the framework of both the one-pion-exchange (OPE) model and the one-boson-exchange (OBE) model. After careful treatment of the S-D wave…
We present a study of the radiative decays of X(3872) at Belle. In the \chi_{c1}\gamma final state, we got the first evidence of a new particle at 3823 MeV$/c^2$.
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…
We fit the invariant mass distribution of ${X(3872)}\rightarrow{J}/{\psi}\pi^+\pi^-$ from LHCb using the propagator for S-wave near-threshold states in effective field theory. In this way, we can directly determine the $Z$ which measures…
The lineshapes of specific production experiments of the exotic state such as $X(3872)$ with $J^{PC}=1^{++}$ quantum numbers involving triangle singularities have been found to become highly sensitive to the binding energy of weakly bound…
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…
We study $D\bar{D}^*$ ($D^*\bar{D}$) scattering in the framework of unitarized heavy meson chiral perturbation theory with pion exchange and a contact interaction. $^3S_1-$$^3D_1$ mixing effects are taken into account. A loosely bound state…
In this work, we take the $X(3872)$ as the hidden-charm tetraquark state with both isospin $I=0$ and $1$ components, then investigate the strong decays $X(3872)\to J/\psi \pi^+\pi^-$, $J/\psi\omega$, $\chi_{c1}\pi^0$, $D^{*0}\bar{D}^0$ and…
Three more $X$ particles are established in the 2014 Particle Data compared with the 2012 ones. There are now five established $X$ particles named as $X(3872)$, $X(3900)$, $X(4260)$, $X(4360)$, and $X(4660)$. Since the first $X$ particle…