相关论文: Update on Z(4430) and X(3872) at Belle
We discuss how the latest data on X(3872) in B and B_s decays speak about its tetraquark nature. The established decay pattern, including the up to date observations by CMS, are explained by the mixing of two quasi-degenerate, unresolvable,…
We present the interpretation that the recently discovered Z^+(4430) by the Belle Collaboration can be a radial excitation of the cs-bar state. We give an explicit cs-bar candidate for this state by calculating the mass value in our…
We present a search for the decay $X(3872) \to \pi^+\pi^-\pi^0$ in the $(772\pm11)\times10^6$ $\Upsilon(4S)\to B \bar B$ data sample collected at the Belle detector, where the $X(3872)$ is produced in $B^{\pm}\to K^{\pm}X(3872)$ and…
Properties of the charmonium-like state X(3872) are investigated and its nature is discussed as based on the existing experimental data. In particular, we analyse the new data from Belle and BaBar Collaborations and argue that, while the…
In the simple color-magnetic interaction model, we investigate possible ground $cs\bar{c}\bar{s}$ tetraquark states in the diquark-antidiquark basis. We use several methods to estimate the mass spectrum and discuss possible assignment for…
Heavy-light diquarks can be the building blocks of a rich spectrum of states which can accommodate some of the newly observed charmonium-like resonances not fitting a pure c-cbar assignment. We examine this possibility for hidden and open…
I will report on the recent LHCb results on the evidence for the decay $X(3872)\rightarrow\psi(2S) \gamma$, and on the improved measurement of the mass and width of the $Z(4430)^-$, the determination of its quantum numbers and the…
In a search for B --> ccbar gamma K decays with the BaBar detector, where ccbar includes J/psi and psi(2S), and K includes K+, Ks, and K*(892), we find evidence for X(3872) --> J/psi gamma and X(3872) --> psi(2S) gamma with 3.6 sigma and…
We report a search for $X(3872)$ and $X(3915)$ in $B^+ \to \chi_{c1} \pi^0 K^+$ decays. We set an upper limit of $\mathcal{B}(B^+ \to X(3872) K^+) \times \mathcal{B}(X(3872) \to \chi_{c1} \pi^0)$ $ < 8.1 \times 10^{-6}$ and $\mathcal{B}(B^+…
We report the observation of two resonance-like structures in the $\pi^+ \chi_{c1}$ invariant mass distribution near 4.1 GeV in exclusive $B\to K\pi^+\chi_{c1}$ decays. A detailed Dalitz-plot analysis demonstrates that these structures…
A search for double-heavy tetraquark state candidates $X_{cc\bar{s}\bar{s}}$ decaying to $D_{s}^{+}D_{s}^{+}$ and $D_{s}^{*+} D_{s}^{*+}$ is presented for the first time using the data samples of 102 million $\Upsilon(1S)$ and 158 million…
We examine the four-quark structure of the recently discovered charged $Z_c(3900)$, $Z(4430)$, and $X_b(5568)$ states. We calculate the widths of the strong decays $Z_c^+ \to J/\psi \pi^+$ ($\eta_c\rho^+$, $\bar D^0D^{\ast\,+}$, $\bar…
We present a preliminary study of $X(3872)$ and $X(3915)$ in the $B\rightarrow(J/\Psi\omega)K$ decay at Belle. This study is based on MC simulated events on the Belle detector at the KEK asymmetric-energy $e+e-$ collider.
The $X(3872)$ could be a shallow $D\bar D^*$ bound state, a compact four-quark state, or a partially composite particle, i.e. a superposition of the two. We will review how these hypotheses could be tested experimentally, examining…
We report the first observation of $B^0 \to X(3872) (K^{+}\pi^{-})$ and evidence for $B^+ \to X(3872) (K^{0}\pi^{+})$. The product of branching fractions for the former decay mode is measured to be ${\cal B}(B^0 \to X(3872) (K^+ \pi^-))…
The BABAR Collaboration performed a search for xi(2220) production in the initial-state radiation process e^+e^- --> gamma J/psi, J/psi --> gamma K^+K^- or J/psi --> gamma K^0_SK^0_S. No evidence for the xi(2220) resonance has been found.…
The charmonium-like resonance $ Z_c(3900) $ and its excited state $ Z(4430) $ are among the particles that are serious candidates for double heavy tetraquarks. Calculations of different parameters associated with these states both in the…
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 present a dynamical approach for description of the multi-quark states that is based on an effective interaction Lagrangian describing the coupling of hadrons to their constituent quarks. First, we explore the consequences of treating…
The X(3872) and Y(3940) properties and decay modes from Belle are reviewed and the results on a search for the decay $B^+\ra h_c K^+$, $h_c\ra \eta_c \gamma$ at Belle are presented.