arXiv subjects

Zhu Zhou

Publications and source records attributed to Zhu Zhou.

3 recordsLinked to original sources

arXiv2015

Hunting for the $X_b$ via hidden bottomonium decays

In this work, we study the isospin conserved hidden bottomonium decay of $X_b\to Υ(1S)ω$, where $X_b$ is taken to be the counterpart of the famous $X(3872)$ in the bottomonium sector as a candidate for the meson-meson molecule. Since it is likely that the $X_b$ is below the $B\bar B^*$ threshold and the mass difference between the neutral and charged bottom meson is small compared to the binding energy of the $X_b$, the isospin violating decay mode $X_b\to Υ(nS)π^+π^-$ would be greatly suppressed. We use the effective Lagrangian based on the heavy quark symmetry to explore the rescattering mechanism of $X_b\to Υ(1S)ω$ and calculate the partial widths. Our results show that the partial width for the $X_b\to Υ(1S)ω$ is about tens of keVs. Taking into account the fact that the total width of $X_b$ may be smaller than a few MeV like $X(3872)$, the calculated branching ratios may reach to orders of $10^{-2}$. These hidden bottomonium decay modes are of great importance in the experimental search for the $X_b$ particularly at the hadron collider. Also, the associated studies of hidden bottomonium decays $X_b \to Υ(nS) γ$, $Υ(nS)ω$, and $B\bar B γ$ may help us investigate the structure of $X_b$ deeply. The experimental observation of $X_b$ will provide us with further insight into the spectroscopy of exotic states and is helpful to probe the structure of the states connected by the heavy quark symmetry.

hep-ph↗

arXiv2014

Investigations on the charmless decays of $Y(4260)$

Apart from the charmful decay channels of $Y(4260)$, the charmless decay channels of $Y(4260)$ also provide us a good platform to study the nature and the decay mechanism of $Y(4260)$. In this paper, we propose to probe the structure of $Y(4260)$ through the charmless decays $Y(4260)\to VP$ via intermediate $D_1\bar D+c.c.$ meson loops, where $V$ and $P$ stand for light vector and pseudoscalar mesons, respectively. Under the molecule ansatz of $Y(4260)$, the predicted total branching ratio $BR_{VP}$ for all $Y(4260)\to VP$ processes are about $(0.34^{+0.32}_{-0.23})%$ to $(0.75^{+0.72}_{-0.52})%$ with the cutoff parameter $α=2\sim 3$. Numerical results show that the intermediate $D_1 \bar D+c.c.$ meson loops may be a possible transition mechanism in the $Y(4260)\to VP$ decays. These predicted branching ratios are the same order to that of $Y(4260) \to Z_c^+(3900) π^-$, which may be an evidence of $D_1D$ molecule and can be examined by the forthcoming BESIII data in the near future.

hep-ph↗

arXiv2014

More hidden heavy quarkonium molecules and their discovery decay modes

To validate the molecular description of the observed $Z_b(10610)/Z_b(10650)$ and $Z_c(3900)/Z_c(4025)$, it is valuable to investigate their counterparts, denoted as $Z_{QV}^{(\prime)}$ in this work, and the corresponding decay modes. In this work, we present an analysis of the $Z_{QV}^{(\prime)}$ using flavor symmetry. We also use the effective Lagrangian based on the heavy quark symmetry to explore the rescattering mechanism and calculate the partial widths for the isospin conserved channels $Z_{QV}^{(\prime)} \to η_Q V$. The predicted partial widths are of an order of MeV for $Z_{QV} \to η_Q V$, which correspond to branching ratios of the order of $10^{-2}\sim 10^{-1}$. For $Z_{QV}^\prime \to η_Q V$, the partial widths are a few hundreds of keV and the branching ratios are about $10^{-3}$. Future experimental measurements can test our predictions on the partial widths and thus examine the molecule description of heavy quarkoniumlike exotic states.

hep-ph↗