arXiv subjects

Qing-Hua Shen

Publications and source records attributed to Qing-Hua Shen.

8 recordsLinked to original sources

arXiv2026

The dynamically generated $h_1$ state by the $K^\bar{K}^$ interaction and its $K_1(1270)\bar{K}$ and $b_1(1235)π$ decays

We investigate the dynamically generated $h_1$ state with spin-parity $J^P = 1^+$ and a mass around 1790~MeV, arising from the $K^* \bar{K}^*$ interaction within the chiral unitary approach. The partial decay widths into the $K_1(1270)\bar{K}$ and $b_1(1235)π$ channels are calculated via a triangular loop mechanism. In this mechanism, the $h_1$ state couples to $K^* \bar{K}^*$, and final-state interactions between $K^*$ and $\bar{K}^*$ proceed through pseudoscalar-meson exchange, leading to the final states $\bar{K}$ (or $π$) and $K_1(1270)$ [or $b_1(1235)$]. We also present the invariant mass distributions of a vector meson and a pseudoscalar meson originating from the decays of $K_1(1270)$ or $b_1(1235)$, along with the corresponding decay widths. Our results show that these decay widths are all of the order of a few MeV. We hope that future experiments can test the predictions presented here, thereby helping to identify this $h_1$ state.

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arXiv2026

Radiative decays of the $Ω(2012)$ as a hadronic molecule

We present a theoretical investigation of the radiative decay process $Ω(2012) \to γΩ$, where the $Ω(2012)$ resonance with spin-parity $J^P=\frac{3}{2}^-$, is treated as a dynamically generated state from $\bar{K}Ξ(1530)$ and $ηΩ$ in $s$-wave and $\bar{K}Ξ$ in $d$-wave. The radiative decay width of the $Ω(2012)$ is calculated using a triangular loop mechanism, where the $Ω(2012)$ couples to the $\bar{K} Ξ(1530)$ channel. Subsequently, the final state interactions between $Ξ(1530)$ and $\bar{K}$ transition to a photon and $Ω$ through the exchange of a $Ξ$ baryon. Our calculations yield a radiative decay width of $13.2 ^{+4.5}_{-3.9}$ KeV, with uncertainties arising from the model parameters. This result provides valuable insights into the nature of the $Ω(2012)$ resonance and its decay dynamics. It is expected that the calculations presented here could be verified by future experiments, which would open a new door for studying the still elusive nature of the $Ω(2012)$.

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arXiv2025

Shedding light on the nature of $ϕ(2170)$ state in the $e^+e^- \to ϕπ^+π^-$ reaction

We investigate the production of $ϕ(2170)$ state in the $e^+e^- \to ϕπ^+π^-$ reaction with the effective Lagrangian approach. In addition to the tree level contributions from the $ϕ(1680)$ meson and a possible X(1750) state, we consider also the $K_1$-$K$-$\bar{K}$ intermediate state process from the perspective of triangular singularity. Based on the one-photon exchange approximation, a pair of $K_1 \bar{K}$ mesons was firstly produced, and then the $K_1$ meson subsequently decays into $ϕ$ and $K$, and the $K\bar{K}$ pair produce the $π^+ π^-$ through the final state interactions, in which the scalar meson $f_0(980)$ is dynamically generated. We show that the inclusion of the triangle loop diagrams leads to a good description of the new BESIII measurements, especially for the structure of $ϕ(2170)$. This provides a novel interpretation of the $ϕ(2170)$ state, offering new insights into its fundamental nature which is still unclear. Furthermore, it is found that these measurements on the $e^+e^- \to ϕπ^+π^-$ reaction can be used to determine some of the properties of two $K_1$ mesons with masses around 1610 MeV and 1895 MeV, which are crucial to reproduce the experimental data.

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arXiv2025

Strong decays of $a_0$, $f_0$, $f_2$, and $K^*_2$ resonances as dynamically generated states of two vector mesons

The two-body strong decays of the $f_0(1500)$, $f_0(1710)$, $a_0(1710)$, $f_2(1270)$, $f_2'(1525)$, and $K_2^*(1430)$ resonances are investigated, assuming them as dynamically generated states of two vector mesons via $s$-wave interactions. The partial decay widths of all the possible two-body pseudoscalar meson-pseudoscalar meson final states are calculated considering the triangular diagrams. It is found that the ratios of branching fractions are similar to the previous results for most channels, which were obtained by using the real-axis method and considering the box diagrams. However, there are also differences. In addition, our focus is on the partial decay widths. More precise experimental measurements are needed to test the model calculations and determine the nature of these scalar and tensor mesons. It is anticipated that the BES\uppercase\expandafter{\romannumeral3}, Belle\uppercase\expandafter{\romannumeral2} and LHCb collaborations will conduct these measurements in the future.

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arXiv2024

Dynamically generated states from the $ηK^\bar{K}^$, $πK^\bar{K}^$, and $K K^\bar{K}^$ systems within the fixed-center approximation

The three-body systems $ηK^* \bar{K}^*$, $πK^* \bar{K}^*$, and $K K^* \bar{K}^*$ are further investigated within the framework of fixed-center approximation, where $K^* \bar{K}^*$ is treated as the fixed-center, corresponding to the possible scalar meson $a_0(1780)$ or the tensor meson $f_2'(1525)$. The interactions between $η$, $π$, $K$, and $K^*$ are taken from the chiral unitary approach. The resonance structures appear in the modulus squared of the three-body scattering amplitude and suggest that $η/ π/ K$-$(K^*\bar{K}^*)_{a_0(1780)/f'_2(1525)}$ hadron state can be formed. By scattering the $η$ meson on the fixed-center $(K^* \bar{K}^*)_{a_0(1780)}$, it is found that there is a distinct peak around 2100 MeV, as shown in the modulus squared of the three-body scattering amplitude, which can be associated with the meson $π(2070)$. For the scattering of the $η$ meson on the $(K^* \bar{K}^*)_{f_2'(1525)}$, a resonance structure around 1890 MeV is found and it can be associated with the $η_2(1870)$ meson. Other resonance structures are also found and can be associated with $π_2(1880)$ and $η(2010)$.

hep-ph↗

arXiv2023

Theoretical study on $Λ_c^+ \to ΛK^+\bar{K}^0$ decay and $Ξ^*(1690)$ resonance

We present a theoretical study of $Ξ^*(1690)$ resonance in the $Λ_c^+ \to ΛK^+ \bar{K}^0$ decay, where the weak interaction part proceeds through the Cabibbo-favored process $c \to s + u\bar{d}$. Next, the intermediate two mesons and one baryon state can be constructed with a pair of $q\bar{q}$ with the vacuum quantum numbers. Finally, the $Ξ^*(1690)$ is mainly produced from the final state interactions of $\bar{K}Λ$ in coupled channels, and it is shown in the $\bar{K}Λ$ invariant mass distribution. Besides, the scalar meson $a_0(980)$ and nucleon excited state $N^*(1535)$ are also taken into account in the decaying channels $K^+\bar{K}^0$ and $K^+Λ$, respectively. Within model parameters, the $K^+ \bar{K}^0$, $\bar{K}^0 Λ$ and $K^+ Λ$ invariant mass distributions are calculated, and it is found that our theoretical results can reproduce well the experimental measurements, especially for the clear peak around $1690$ MeV in the $\bar{K}Λ$ spectrum. The proposed weak decay process $Λ_c^+ \to ΛK^+ \bar{K}^0$ and the interaction mechanism can provide valuable information on the nature of the $Ξ^*(1690)$ resonance.

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arXiv2022

Faddeev fixed-center approximation to the $ηK^\bar{K}^$, $πK^\bar{K}^$ and $KK^\bar{K}^$ systems

The three-body $ηK^*\bar{K}^*$, $πK^*\bar{K}^*$ and $KK^*\bar{K}^*$ systems are investigated within the framework of fixed-center approximation to the Faddeev equations, where $K^*\bar{K}^*$ is treated as the scalar meson $f_0(1710)$. The interactions between $π$, $η$, $K$ and $K^*$ are taking from the chiral unitary approach. By scattering the $η$ meson on the clusterized $(K^*\bar{K}^*)_{f_0(1710)}$ system, we find a peak in the modulus squared of the three-body scattering amplitude and it can be associated as a bound state with quantum numbers $I^G(J^{PC})=0^+(0^{-+})$. Its mass and width are around 2054 MeV and 60 MeV, respectively. This state could be associated to the $η(2100)$ meson. For the $π(K^*\bar{K}^*)_{f_0(1710)}$ scattering, we find a bump structure around 1900-2000 MeV with quantum numbers $1^-({0^{-+}})$. While for the $K K^* \bar{K}^*)_{f_0(1710)}$ system, there are three structures. One of them is much stable and its mass is about 2130 MeV. It is expected that these theoretical predictions here could be tested by future experimental measurements, such as by the BESIII, BelleII and LHCb collaborations.

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arXiv2022

Faddeev fixed-center approximation to the $D\bar{D}K$ system and the hidden charm $K_{c\bar{c}}(4180)$ state

We perform a theoretical study on the $D\bar{D}K$ three body system, using the fixed center approximation to the Faddeev equations, considering the interaction between $D$ and $K$, $D$ and $\bar{D}$ from the chiral unitary approach. We assume the scattering of $K$ meson on a clusterized system $D\bar{D}$, where a scalar meson $X(3720)$ could be formed. Thanks to the strong $DK$ interaction, where the scalar $D^*_{s0}(2317)$ meson is dynamically generated, a resonance structure shows up in the modulus squared of the three body $K$-$(D\bar{D})_{X(3720)}$ scattering amplitude and supports that a $D\bar{D}K$ bound state can be formed. The result is in agreement with previous theoretical studies, which claim a new excited hidden charm $K$ meson, $K_{c\bar{c}}(4180)$ with quantum numbers $I(J^P) = \frac{1}{2}(0^-)$ and mass about $4180$ MeV. It is expected that these theoretical results motivate its search in experimental measurements.

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