How to understand the underlying structures of X(4140)X(4140), X(4274)X(4274), X(4500)X(4500) and X(4700)X(4700)

We investigate the possible rescattering effects which may contribute to the process $B^+\to J/\psi\phi K^+$. It is shown that the $D_{s}^{*+}D_{s}^-$ rescattering via the open-charmed meson loops, and $\psi^\prime \phi$ rescattering via the $\psi^\prime K_1$ loops may simulate the structures of $X(4140)$ and $X(4700)$, respectively. However, if the quantum numbers of $X(4274)$ ($X(4500)$) are $1^{++}$ ($0^{++}$), it is hard to to ascribe the observation of $X(4274)$ and $X(4500)$ to the $P$-wave threshold rescattering effects, which implies that $X(4274)$ and $X(4500)$ could be genuine resonances. We also suggest that $X(4274)$ may be the conventional orbitally excited state $\chi_{c1}(3P)$.Comment: 14 pages, 5 figures, 1 tabl

Investigating possible decay modes of Y(4260)Y(4260) under the D1(2420)Dˉ+c.cD_1(2420)\bar D +c.c molecular state ansatz

By assuming that $Y(4260)$ is a $D_1\bar D$ molecular state, we investigate some hidden-charm and charmed pair decay channels of $Y(4260)$ via intermediate $D_1\bar D$ meson loops with an effective Lagrangian approach. Through investigating the $\alpha$-dependence of branching ratios and ratios between different decay channels, we show that the intermediate $D_1 \bar D$ meson loops are crucial for driving these transitions of $Y(4260)$ studied here. The coupled channel effects turn out to be more important in $Y(4260) \to D^{*}\bar{D}^{*}$, which can be tested in the future experiments.Comment: 8 pages, 6 figures; The width effects of Y(4260) considered; Revised version accepted by Phys. Rev.