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Yu-Hui Zhou

Publications and source records attributed to Yu-Hui Zhou.

7 recordsLinked to original sources

On Compositeness of $D_{s0}^*(2317)$ and its decay to $D_s\pi^0$

We demonstrate that the $D_{s0}^{*}(2317)$ can be described as a bound-state pole arising from the coupling between a discrete $c\bar{s}(1^3P_0)$ state and the $DK$ continuum state in the Lee-Friedrichs model. The elementariness and compositeness of the $D_{s0}^{*}(2317)$ are determined to be about $Z:X\approx 51.1 \%:48.9\%$, indicating a nearly equal admixture of compact quark-model state and hadronic molecular components. The decay width of $D_{s0}^{*}(2317)\rightarrow D_s^{+}\pi^0$ is evaluated within the quark rearrangement framework. The transition $c\bar{s}(1^3P_0)\rightarrow D_s\pi^0$ proceeds via the OZI-allowed $c\bar{s}(1^3P_0)-D_s\eta$ coupling followed by $\eta-\pi^0$ mixing, which serves as the primary source of isospin violation in this channel. The coupling between $DK$ and $D_s\pi^0$ is computed in a quark rearrangement model, where the isospin violation effect originates from the mass difference between the $D^0K^+$ and $D^+K^0$ thresholds. The parameters of the scheme shares the same ones with those of the underlying potential model and only the vacuum production strength is adjusted to reproduce the physical $D_{s0}^{*}(2317)$ mass. This calculation may shed more insight to the nature of exotic $D_{s0}^{*}(2317)$ state and its isospin-breaking decay properties.

hep-ph

Comparing relativistic and non-relativistic quark pair creation models

We investigate the strong decay properties of light unflavored and strange mesons within a relativistic quark-pair-creation (QPC) framework, and compare the results with those obtained in the conventional non-relativistic QPC model. Our analysis shows that, within the present theoretical and experimental uncertainties, the relativistic QPC model yields predictions for strong decay widths of comparable overall quality to those of the non-relativistic QPC model. This indicates that the non-relativistic QPC approach remains adequate for estimating decay widths in most practical applications. Nevertheless, owing to the inclusion of Lorentz boosts and Wigner rotations, the relativistic QPC model exhibits a stronger suppression of decay amplitudes in the high-energy region. This feature may be useful in studies based on unquenched quark models, where the relativistic QPC coupling could lead to more controlled meson-loop effects and mass shifts.

hep-ph

Understanding the 1P- and 2S-wave nucleon resonances within the extended Lee-Friedrichs Model

We present a unified desciption of the low-lying $1P$- and $2S$-wave nucleon resonance within the framework of an extended Lee-Friedrichs scheme. By incorporating the coupled-channel dynamics between bare quark-model states and the $\pi N$, $\pi\Delta$ and $\eta N$ meson-baryon continua, we examine the mass shifts and structural properties of these excited states. We demonstrate that when the model parameters are calibrated to match the $1P$-wave spectrum and their widths, the pole associated with the bare $2S$ state is naturally shifted downward to the mass region of physical Roper resonance--$N(1440)$, thereby offering a dynamical explanation for the long-standing level-inversion problem. An approximate analysis of compositeness and elementariness reveals that the Roper resonance contains a significant meson-baryon continuum states, consistent with the picture of a bare core heavily dressed by meson-baryon cloud. Simultaneously, the pole positions and properties of five $1P$-wave resonances--$N(1535)$, $N(1650)$, $N(1520)$, $N(1700)$ and $N(1675)$ are successfully reproduced. Our results highlight the essential role of coupled-channel effects in shaping the nucleon spectrum and provide a consistent microscopic insight into the interplay between internal quark degrees of freedom and external hadronic fields.

hep-ph

Updated analysis of charmonium states in a relativized quark potential model

Motivated by recent experimental observations of charmonium(-like) states, we investigate their interpretation as conventional charmonium states within the framework of relativized quark potential model. We find a consistent description of the updated masses of charmonia, bottomonia and some selected charmed mesons, then systematically compute open-charm strong decay widths and electromagnetic transition widths for radially excited charmonium states up to $n=5$. The numerical results show significantly improved agreement with experimental masses and widths. Notably, the newly-observed $\chi_{c1}(4010)$ and $\chi_{c1}(4274)$ are tentatively associated with the $\chi_{c1}(2P)$ and $\chi_{c1}(3P)$ respectively, while the $\chi_{c0}(4500)$ and $\chi_{c0}(4700)$ are interpreted as the $\chi_{c0}(4P)$ and $\chi_{c0}(5P)$ states. For the controversial $\chi_{c1}(3872)$ state, we suggest its potential connection to $\chi_{c1}(4010)$, as a two-pole structure due to the $\chi_{c1}(2P)$ coupling to $D\bar{D}$ channels. Intriguingly, the predicted mass of $\chi_{c0}(2P)$ is about 3851 MeV, diverging from the original estimate of 3916 MeV in the Godfrey and Isgur's work but consistent with non-relativistic potential model predictions. This calculation might provide more insight to the future experimental investigation of charmonium(-like) states.

hep-ph

Strong decays of low-lying $D$-wave $Ξ_b/Ξ_b'$ baryons with QPC model

For further decoding the inner structure of the two excited $Ξ_b$ states observed by LHCb, we perform a systematical study of the strong decays of the low-lying $1D$-wave $Ξ_b$ and $Ξ_b'$ excitations using the quark pair creation model within the $j-j$ coupling scheme. Combining with the measured masses and decay properties of $Ξ_{b}(6327)^{0}$ and $Ξ_{b}(6327)^{0}$, the two excited states can be explained as $1D$ $λ$-mode $Ξ_b$ states $Ξ_{b}|J^{P}=\frac{3}{2}^{+},2\rangle_{λλ}$ and $Ξ_{b}|J^{P}=\frac{5}{2}^{+},2\rangle_{λλ}$, respectively. If such a view were correct, $Ξ_b'π$ and $Ξ_b'^*π$ could be another interesting channels for experimental exploring of the $Ξ_{b}(6327)^{0}$ and $Ξ_{b}(6327)^{0}$, respectively. Those calculations are good consistent with the results within the chiral quark model. In addition, for the other missing $1D$-wave $Ξ_b$ and $Ξ_b'$ excitations, our predictions indicate that:(i) the two $ρ$-mode $1D$ $Ξ_b$ states are likely to be moderate states with a width of $Γ\sim50$ MeV. The $J^P=3/2^+$ state dominantly decays into $Σ_bK$ and $Ξ_b'π$, while the $J^P=5/2^+$ state decays primarily through $Σ_b^*K$ and $Ξ_b'^*π$. (ii) The $λ$-mode $1D$ $Ξ_b'$ states may be moderate states with a widths of about several to dozens of MeV. Most of the $λ$-mode $1D$ $Ξ_b'$ states mainly decay into the $1P$-wave bottomed baryon via the pionic decay processes. Meanwhile, several $λ$-mode $1D$ $Ξ_b'$ states have significant decay rates into $ΛB$. (iii) While, the $ρ$-mode $1D$ $Ξ_b'$ states are predicted to be very broad states with a width of about several hundreds MeV. It will be a great challenge to explore the $ρ$-mode $1D$ $Ξ_b'$ states in experiments for their broad widths.

hep-ph

Strong decays of the low-lying $1P$- and $1D$-wave $Σ_c$ baryons

In this work, we systematically study the OZI-allowed two-body strong decay properties of $1P$- and $1D$-wave $Σ_c$ baryons within the $j $-$j$ coupling scheme in the framework of the quark pair creation model. For a comparison, we also give the predictions of the chiral quark model. Some model dependencies can be found in the predictions of two models. The calculations indicate that: (i) The $1P$-wave $λ$-mode $Σ_c$ states most likely to be relatively narrow states with a width of $Γ<80$ MeV. Their main decay channels are $Λ_cπ$, or $Σ_cπ$, or $Σ_c^*π$. The $1P$-wave $ρ$-mode states most might be broad states with a width of $Γ\sim 100-200$ MeV. They dominantly decay into $Σ_cπ$ and $Σ_c^*π$ channels. Some evidences of these $1P$-wave states are most likely to be observed in the $Λ_cπ$ and $Λ_cππ$ invariant mass spectra around the energy range of $2.75-2.95$ GeV. (ii) The $1D$-wave $λ$-mode $Σ_c$ excitations may be moderate states with a width of about dozens of MeV. The $1D$-wave $λ$-mode states mainly decay into the $1P$-wave charmed baryon via the pionic decay processes. Meanwhile, several $1D$-wave $λ$-mode states have significant decay rates into $DN$ or $D^*N$. Hence, the $DN$ and $D^*N$ are likely to be interesting channels for experimental exploration. (iii) Furthermore, the two $1D$-wave $ρ$-mode excitations $Σ_c|J^P=5/2^+,3\rangle_{ρρ}$ and $|J^P=7/2^+,3\rangle_{ρρ}$ are most likely to be fairly narrow state with a width of dozens of MeV, and they mainly decay into $Λ_cπ$. Some evidences of them might be observed in the $Λ_cπ$ invariant mass spectra around the energy range of $3.1-3.2$ GeV.

hep-ph

The $1D$-wave bottom-strange baryons and possible interpretation of $Ξ_{b}(6327)^{0}$ and $Ξ_{b}(6333)^{0}$

Inspired by the LHCb's newest observation of two new excited $Ξ_b^0$ states, we systematically study the strong decays of the low-lying $λ$- and $ρ$-modes $1D$-wave $Ξ_{b}$ and $Ξ^{'}_{b}$ baryons using the chiral quark model within the $j$-$j$ coupling scheme. Based on the measured masses and strong decay properties of $Ξ_{b}(6327)^{0}$ and $Ξ_{b}(6333)^{0}$, we explain the two states as the $λ$-mode $1D$ $Ξ_{b}$ states with $ J^{P}=3/2^{+} $ and $ J^{P}=5/2^{+} $, respectively. Moreover, under this assignment, another dominant decay channel of $Ξ_{b}(6327)^{0}$ is $Ξ'_bπ$ and that of $Ξ_{b}(6333)^{0}$ is $Ξ_b^*π$. Hence, the decay modes $Ξ'_bπ$ and $Ξ_b^*π$ may be another ideal channels as well to decode the inner structure of $Ξ_{b}(6327)^{0}$ and $Ξ_{b}(6333)^{0}$, respectively. For other unseen $1D$ $Ξ_b$ and $Ξ'_b$ states, our results indicate: (i) $Ξ_b|J^P=\frac{3}{2}^+,2\rangle_ρ$ and $Ξ_b|J^P=\frac{5}{2}^+,2\rangle_ρ$ are most likely to be narrow states with a width of $Γ\simeq(12-30)$ MeV, and dominantly decay into $Σ_bK$ and $Σ^*_bK$, respectively; (ii) The $1D$ $Ξ'_b$ baryons are not broad states, and the widths vary in the range of $Γ\simeq(14-46)$ MeV. These states have a good potential to be observed in their dominant decay processes.

hep-ph