arXiv subjects

HongQiang Zhu

Publications and source records attributed to HongQiang Zhu.

4 recordsLinked to original sources

arXiv2021

Radiative decay of the $Ξ(1620)$ in a hadronic molecule picture

Last year, the $Ξ(1620)$ state that is cataloged in the Particle Data Group (PDG) with only one star is reported again in the $Ξ^{-}π^{+}$ final state by the Belle Collaboration. Its properties not only the spectroscopy but also the decay width cannot be simply explained in the context of conventional constituent quark models. This intrigues an active discussion on the structure of this resonance. In this work, we study the radiative decays of the newly observed $Ξ(1620)$ assuming that it is a meson-baryon molecular state of $Λ\bar{K}$ and $Σ\bar{K}$ with spin-parity $J^P=1/2^{-}$ in our previous work. The partial decay widths of the $Λ\bar{K}-Σ\bar{K}$ molecular state into $Ξγ$ and $Ξπγ$ final states through hadronic loops are evaluated with the help of the effective Lagrangians. The partial widths for the $Ξ(1620)^0\toγΞ$ and $Ξ(1620)^0\toγΞπ$ are evaluated to be about $118.76-174.21$ KeV and $58.19-68.75$ eV, respectively, which may be accessible for the LHCb. If the $Ξ(1620)$ is $Λ\bar{K}-Σ\bar{K}$ molecule, the radiative transition strength $Ξ(1620)^0\toγ\bar{K}Λ$ is quite small and the decay width is of the order of 0.01 eV. Future experimental measurements of these processes can be useful to test the molecule interpretations of the $Ξ(1620)$.

hep-ph↗

arXiv2020

Description of the newly observed $Ξ_c^{0}$ states as molecular states

Very recently, three new structures $Ξ_c(2923)^0$, $Ξ(2938)^0$, and $Ξ(2964)^0$ at the invariant mass spectrum of $Λ_c^{+}K^{-}$ observed by the LHCb Collaboration triggers a hot discussion about their inner structure. In this work, we study the strong decay mode of the newly observed $Ξ_c$ assuming that the $Ξ_c$ is a $\bar{D}Λ-\bar{D}Σ$ molecular state. With the possible quantum numbers $J^p=1/2^{\pm}$ and $3/2^{\pm}$, the partial decay widths of the $\bar{D}Λ-\bar{D}Σ$ molecular state into the $Λ_c^{+}K^{-}$, $Σ_c^{+}K^{-}$,and $Ξ_c^{+}π^{-}$ final states through hadronic loop are calculated with the help of the effective Lagrangians. By comparison with the LHCb observation, the current results of total decay width support the $Ξ(2923)^0$ as $\bar{D}Λ-\bar{D}Σ$ molecule while the decay width of the $Ξ_c(2938)^0$ and $Ξ(2964)^0$ can not be well reproduced in the molecular state picture. In addition, the calculated partial decay widths with $S$ wave $\bar{D}Λ-\bar{D}Σ$ molecular state picture indicate that allowed decay modes, $Ξ_c^{+}π^{-}$, may have the biggest branching ratios for the $Ξ_c(2923)$. The experimental measurements for this strong decay process could be a crucial test for the molecule interpretation of the $Ξ_c(2923)$.

hep-ph↗

arXiv2020

Radiative decay of $Ξ_b(6227)$ in a hadronic molecule picture

The $Ξ_b(6227)$ baryon with the quantum number $J^P=1/2^{-}$ is considered as a molecular state composed of a $Σ_b$ baryon and $\bar{K}$ meson. The partial decay widths of the $Σ_b\bar{K}$ molecular state into $Ξ_bγ$ and $Ξ_b^{'}γ$ final states through hadronic loops are evaluated with the help of the effective Lagrangians. The partial widths for the $Ξ_b(6227)\toγΞ_b$ and $Ξ_b(6227)\toγΞ^{'}_b$ are evaluated to be about 1.50-1.02 KeV and 17.56-24.91 KeV, respectively, which may be accessible for the LHCb. Based on our results we argue that an experimental determination of the radiative decay width of $Ξ_b(6227)$ is important for the understanding of its intrinsic properties.

hep-ph↗

arXiv2019

Production of the $D_{s0}(2317)$ and $D_{s1}(2460)$ by kaon-induced reactions on a proton target

We investigate the possibility to study the charmed-strange mesons $D_{s0}(2317)$ and $D_{s1}(2460)$ by kaon-induced reactions on a proton target in an effective Lagrangian approach. The production process is described by the $t$-channel $D^{0}$ and $D^{*0}$ exchanges, respectively. Our theoretical approach is based on the chiral unitary theory where the $D_{s0}(2317)$ and $D_{s1}(2460)$ resonances are dynamically generated. Within the coupling constants of the $D_{s0}(2317)$ to $KD$ and $D_{s1}(2460)$ to $KD^{*}$ channels obtained from the chiral unitary theory, the total and differential cross sections of the $K^{-}p\to{}Λ_cD_{s0}(2317)$ and $K^{-}p\to{}Λ_cD_{s1}(2460)$ are evaluated. The $\bar{K}p$ initial state interaction mediated by Pomeron and Reggeon exchanges is also included, which reduces the production cross sections of the $D_{s0}(2317)$ and $D_{s1}(2460)$. If measured in future experiments, the predicted total cross sections and specific features of the angular distributions can be used to test the (molecular) nature of the $D_{s0}(2317)$ and $D_{s1}(2460)$.

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