arXiv subjects

Ru-Min Wang

Publications and source records attributed to Ru-Min Wang.

At least 19 recordsLinked to original sources

arXiv2026

Studying the tensor resonance contributions in $B \to PP\ell^+\ell^-$ and $B \to PV\ell^+\ell^-$ decays

We analyze the semileptonic $B \to T\ell^+\ell^-$, $B \to T(\to PP)\ell^+\ell^-$, and $B \to T(\to PV)\ell^+\ell^-$ decays with $\ell=e,\mu,\tau$ based on flavor SU(3) analysis in the standard model ($T$ denotes the light tensor meson, $P$ denotes the light pseudoscalar meson, and $V$ denotes the light vector meson). The hadronic amplitudes of the $B \to T\ell^+\ell^-$ decays are related by the nonperturbative parameters, and all branching ratios of the $B \to T\ell^+\ell^-$ decays are obtained by the experimental data of the branching ratio of $B^0_s\to f^{\prime}_{2}(1525)\mu^+\mu^-$ in three cases, and then the branching ratios of the $B \to T(\to PP)\ell^+\ell^-$ and $B \to T(\to PV)\ell^+\ell^-$ decays are predicted by the narrow width approximation and further considering finite width effects of the intermediate resonances. Compared with the narrow width results, the finite width effects slightly reduce the branching fractions for most decays. However, sizeable finite width effects are found in some near threshold modes. For the subthreshold $K_2^*(1430)\to K\eta'$ relevant channels, the finite width of the tensor resonance can open a nonzero contribution. Compared with the measured $B \to PP\ell^+\ell^-$ and $B \to PV\ell^+\ell^-$ decays, we find that the branching ratios with the tensor resonance states are small. Therefore, other resonances, for example, the vector mesons, the scalar mesons, the axial-vector mesons or their excited states, might give the dominant contributions to the relevant decays. Our results might be tested in current and future experiments.

hep-ph↗

arXiv2026

Study of $\chi _{c1,2}$ decays to $PPP$ via light meson resonances

The three-body decays of charmonium states provide a valuable laboratory for probing non-perturbative QCD dynamics and investigating light meson resonances. Three-body decays $\chi _{c1,2} \to P_{1}P_{2}P_{3}$ are studied in this work ($P$ denotes the light pseudoscalar meson). Branching ratio analysis is performed for the $\chi _{c1,2} \to P_{1}P_{2}P_{3}$ decays incorporating light vector ($V$) meson resonance, light tensor ($T$) meson resonance and light scalar ($S$) meson resonance contributions. Based on the SU(3) flavor symmetry approach, we calculate the branching ratios under both the narrow width approximation and the finite width effect, and provide the predict results in the $\chi _{c1,2}\to (V/T)P_{3} \to P_{1}P_{2}P_{3}$ processes. Furthermore, based on the significant $a^{+}_{0}(980)$ resonance signal in $\chi _{c1} \to \pi^{+ }\pi^{- }\eta$ decay, the predict results for $\chi _{c1}\to SP_{3} \to P_{1}P_{2}P_{3}$ are also obtained. While the resonance signals observed in current experiments are mainly concentrated in the $\chi_{c1} \to \pi^+ \pi^- \eta$ decay, our results suggest potential resonance contributions in other channels. Especially in $\chi _{c1,2}\to KK\pi$ channels, the predicted results show the significant resonance contributions from $V$ mesons and $T$ mesons, which is worth further experimental verification and exploration.

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arXiv2025

Study the decays of $\chi_{cJ}(J=0,1,2)$ to light meson pairs with SU(3) flavor symmetry/breaking analysis

Based on available experimental results on $\chi _{cJ}(J=0,1,2)$ decays, we investigate the $\chi_{cJ}\to PP$, $VV$, $PV$, and $PT$ decays by using SU(3) flavor symmetry/breaking approach, where $P$, $V$, and $T$ denote light pseudoscalar, vector, and tensor mesons, respectively. With the decay amplitude relations determined by SU(3) flavor symmetry/breaking, we present the branching ratios for all $\chi_{cJ}\to PP$ and $\chi_{cJ}\to VV$ modes, including ones without experimental data. While theoretical considerations strongly suppress or even forbid most $\chi_{cJ}\to PV$ and $PT$ decays, we also provide quantitative predictions constrained by existing experimental data. Our results are expected to be accessible in future experiments at BESIII and the planned Super Tau-Charm Facility.

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arXiv2025

Flavor SU(3) analysis of the charmless semileptonic $B \to PV\ell^+\nu_\ell$ decays

All charmless $B \to PV\ell^+\nu_\ell$ ($P$ denotes the light pseudoscalar meson and $V$ denotes the vector meson) decays have not been experimentally observed to date, but some of them might be measured in the near future. The charmless $B \to PV\ell^+\nu_\ell$ decays with the axial-vector ($A$) resonance states, the tensor ($T$) resonance states and the excited vector ($V_{E,D}$) resonance states are studied based on flavor SU(3) analysis in this work, where $V_E$ contains $\{\rho(1450), K^*(1410), \omega(1420), \phi(1680)\}$ with quantum numbers $n^{2S+1}L_J=2^3S_1$ and $V_D$ contains $\{\rho(1700), K^*(1680), \omega(1650), \phi(2170)\}$ with quantum numbers $n^{2S+1}L_J=1^3D_1$. The hadronic amplitudes of the $B \to A/T \ell^+\nu_{\ell}$ decays are related by the nonperturbative parameters, and the branching ratio predictions of $B \to A/T/V_{E,D} \ell^+\nu_{\ell}$ are obtained, and then the branching ratios of the $B\to A(A\to PV)\ell^+\nu_\ell$, $B\to T(T\to PV)\ell^+\nu_\ell$, $B\to V_E(V_E\to PV)\ell^+\nu_\ell$ and $B\to V_D(V_D\to PV)\ell^+\nu_\ell$ are obtained by the narrow width approximation or further considering the width effects. We find that most branching ratios of the $B \to A \ell^+\nu_{\ell}$ decays and many branching ratios of the $B\to A(A\to PV)\ell^+\nu_\ell$ decays are on the order of $\mathcal{O}(10^{-4}-10^{-3})$, and all branching ratios with the tensor resonance states and the excited vector resonance states are small. Our results could be tested in the future BelleII and LHCb experiments.

hep-ph↗

arXiv2025

Estimating of CP Violation in $B_{c}\rightarrow B K^{0}+B {\bar{K}}^0\rightarrow B \pi^{\pm} e^{\mp} \nu_{e}$ Decays

In this paper, we investigate the CP asymmetries ${\mathcal A}_{CP}^{pm}$ and ${\mathcal A}_{CP}^{mp}$ in $B_{c}^{\pm}\rightarrow B^{\pm} K^{0}+B^{\pm} {\bar{K}}^0\rightarrow B^{\pm} \pi^{\pm} e^{\mp} \nu_{e}$ and $B_{c}^{\pm}\rightarrow B^{\pm} K^{0}+B^{\pm} {\bar{K}}^0\rightarrow B^{\pm} \pi^{\mp} e^{\pm} \nu_{e}$ decays, both of them consist of three parts: the indirect CP violations in $K^0 -\bar{K}^0$ mixing $A_{CP,mix}^{pm}$ and $A_{CP,mix}^{mp}$, the direct CP violations in $B_{c}$ decay $A_{CP,dir}^{pm}$ and $A_{CP,dir}^{mp}$, the new CP violation effects $A_{CP,int}^{pm}$ and $A_{CP,int}^{mp}$, which originate from the interference between the amplitude of the $B_{c}^{-}\rightarrow B^{-} K^{0} ({\bar{K}}^0) \rightarrow B^{-} \pi^{-} e^{+} \nu_{e}(\pi^{+} e^{-} \bar{\nu}_{e})$ decay with the difference between the oscillating effect of $K^0\rightarrow {\bar{K}}^0$ and that of ${\bar{K}}^0\rightarrow K^0 $. The strong phase differences of the direct CP asymmetries $A_{CP,dir}^{pm}$ and $A_{CP,dir}^{mp}$ arising from $K^0-\bar{K}^0$ mixing parameters. ${\mathcal A}_{CP}^{pm}$ and ${\mathcal A}_{CP}^{mp}$ are of the order $\mathcal{O}(10^{-4})$ and $\mathcal{O}(10^{-3})$, respectively. The new CP violation effect ${\mathcal A}_{CP,int}^{pm}$ plays a dominant role in ${\mathcal A}_{CP}^{pm}$, the CP asymmetry ${\mathcal A}_{CP}^{mp}$ is dominated by the indirect CP violation ${\mathcal A}_{CP,mix}^{mp}$, so the CP asymmetry ${\mathcal A}_{CP}^{pm}$ provides an ideal place to study the new CP violation effect. We derive another two asymmetry observables ${\mathcal A}_{CP}^{pp}$ and ${\mathcal A}_{CP}^{mm}$, which are dominated by $K^0-\bar{K}^0$ mixing. The observables ${\mathcal A}_{CP}^{pm}$, ${\mathcal A}_{CP}^{mp}$, ${\mathcal A}_{CP}^{pp}$ and ${\mathcal A}_{CP}^{mm}$ are hopefully to be marginally observed at the LHC experiment and the HL-LHC experiment.

hep-ph↗

arXiv2024

Study of semileptonic $B\to DP\ell^+\nu_\ell$ decays based on the SU(3) flavor symmetry

Decays $B\to DP\ell^+\nu_\ell~(\ell=e,\mu,\tau)$ with the non-resonance, the charmed vector resonances, the charmed scalar resonances and the charmed tensor resonances are calculated by using the SU(3) flavor symmetry. Firstly, the decay amplitudes of different modes are related by the SU(3) flavor symmetry. Then, relevant experiential data are used to constrain nonperturbative coefficients in the non-resonant and various resonant $B\to DP\ell^+\nu_\ell$ decays. Finally, using the constrained nonperturbative coefficients, the branching ratios of not-yet-measured $B\to D^*P\ell^+\nu_\ell$ decays with the non-resonant and various charmed resonant contributions are predicted. Many branching ratios are predicted for the first time. We find that $B\to D\eta'\ell^+\nu_\ell, B_s\to D_s\eta'\ell^+\nu_\ell$ decays only receive the non-resonant contributions, $B\to D_sK\ell^+\nu_\ell$, $B_s\to DK\ell^+\nu_\ell$, $B\to D\eta\ell^+\nu_\ell$ and $B_s\to D_s\eta\ell^+\nu_\ell$ decays receive both non-resonant and charmed tensor resonant contributions, $B^+\to D^-\pi^+\ell^+\nu_\ell$ decays receive the non-resonant, the charmed scalar resonant and the charmed tensor resonant contributions, and other $B\to D\pi\ell^+\nu_\ell$ decays receive all four kinds of contributions. These results can be used to test the SU(3) flavor symmetry approach in the four-body semileptonic decays by the future LHCb and Belle-II experiments.

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arXiv2024

Probing $\chi _{cJ}(J=0,1,2)$ decay into baryon and anti-baryon with SU(3) flavor analysis

With the accurate measurements of $\chi _{cJ}(J=0,1,2)$ charmonium decays, we explore $\chi _{cJ}\to \mathcal{B}_{8}\bar{\mathcal{B}}_{8}$ and $\mathcal{B}_{10}\bar{\mathcal{B}}_{10}$ decays based on the SU(3) flavor symmetry model, where $\mathcal{B}_{8}$ and $\mathcal{B}_{10}$ are light octet and decuplet baryons, respectively. The decay amplitude relations are determined by an effective interaction Hamiltonian. Then using experimental data and the amplitude relations of $\chi _{cJ}\to \mathcal{B}_{8}\bar{\mathcal{B}}_{8}$, $\mathcal{B}_{10}\bar{\mathcal{B}}_{10}$ decays, relative nonperturbative coefficients are constrained, and the branching ratios of unmeasured $\chi _{cJ}\to \mathcal{B}_{8}\bar{\mathcal{B}}_{8},\mathcal{B}_{10}\bar{\mathcal{B}}_{10}$, for examples, $\chi _{cJ}\to n\bar{n}$ and $\chi _{cJ}\to\Lambda \bar{\Sigma}^{0}+\bar{\Lambda} \Sigma^{0}$ channels, are predicted. Moreover, we discuss the case of adding a mixing angle between $\Lambda $ and $\Sigma ^{0}$, which is determined by the quark mass differences. Our results provide valuable insights that will aid in advancing our understanding of the mechanisms and characteristics of $\chi _{cJ}$ decays.

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arXiv2024

Study of the axial-vector and tensor resonant contributions to the $D \to VP\ell^+\nu_\ell$ decays based on SU(3) flavor analysis

Semileptonic three-body $D \to M\ell^+\nu_\ell$ decays, non-leptonic $M \to VP$ decays, and semileptonic four-body $D \to M(M \to VP)\ell^+\nu_\ell$ decays are analyzed using the SU(3) flavor symmetry/breaking approach, where $\ell=e/\mu$, $M=A/T$, and $A/T/V/P$ denote the axial-vector/tensor/vector/pseudoscalar mesons, respectively. In terms of SU(3) flavor symmetry/breaking, the decay amplitudes of the $D \to M \ell^+ \nu_\ell$ decays and the vertex coefficients of the $M \to VP$ decays are related. The relevant non-perturbative parameters of the $D \to A\ell^+\nu_\ell$, $A \to VP$ and $T \to VP$ decays are constrained by the present experimental data, and the non-perturbative parameters of $D \to T\ell^+\nu_\ell$ decays are taken from the results in the light-front quark model since no experimental data are available at present. The branching ratios of the $D \to M \ell^+ \nu_\ell $, $M \to VP$, and $D\to M(M\to VP)\ell^+\nu_\ell$ decays are then predicted. We find that some processes receive both tensor and axial-vector resonant contributions, while other processes receive only axial-vector resonant contributions. In cases where both kinds of resonant contributions exist, the axial-vector contributions are dominant. Some branching ratios with axial-vector resonance states are large, and they may be measured experimentally in the near future. In addition, the sensitivities of the branching ratios of $D \to A \ell^+ \nu_\ell $ and $A \to VP$ decays to the parameters are also investigated, and some decay branching ratios are found to be sensitive to the non-perturbative parameters.

hep-ph↗

arXiv2023

Four-body Semileptonic Charm Decays $D\to P_1P_2\ell^+ν_\ell $ Based on SU(3) Flavor Analysis

Motivated by the significant experimental progress in probing semileptonic decays $D\to P_1P_2\ell^+ν_\ell~(\ell=μ,e)$, we analyze the branching ratios of the $D\to P_1P_2\ell^+ν_\ell $ decays with the non-resonant, the light scalar meson resonant and the vector meson resonant contributions in this work. We obtain the hadronic amplitude relations between different decay modes by the SU(3) flavor analysis, and then predict relevant branching ratios of the $D\to P_1P_2\ell^+ν_\ell$ decays by the present experimental data with $2 σ$ errors. Most of our predicted branching ratios are consistent with present experimental data within $2σ$ error bars, and others are consistent with the data within $3σ$ error bars. We find that some branching ratios of the non-resonant decays are on the order of $\mathcal{O}(10^{-3}-10^{-4})$, the vector meson resonant contributions are dominant in many decays, the non-resonant, the vector meson resonant and the scalar resonant contributions are all important in the $D^0\toηπ^-\ell^+ν_\ell$ decays, and both the non-resonant and the scalar resonant contributions are important in the $D^0\to K^-K^0\ell^+ν_\ell,η'π^-\ell^+ν_\ell$ and $D^+\to \overline{K}^0K^0\ell^+ν_\ell,π^0π^0\ell^+ν_\ell,ηπ^0\ell^+ν_\ell,η'π^0\ell^+ν_\ell$ decays. According to our predictions, many decay modes could be observed in the experiments like BESIII, LHCb and BelleII, and some decay modes might be measured in these experiments in near future.

hep-ph↗

arXiv2023

Study of CP Violation in $D^{\pm}\rightarrow K^{\ast}(892)^{0} π^{\pm} + \bar{K}^{\ast }(892)^{0}π^{\pm}\rightarrow K_{S,L}^{0}π^0 π^{\pm}$ Decays

Within the Standard Model, we investigate the CP violations and the $K_S^0-K_L^0$ asymmetries in $D^{\pm}\rightarrow K^{\ast}(892)^{0} π^{\pm} + \bar{K}^{\ast }(892)^{0}π^{\pm}\rightarrow K_{S,L}^{0}π^0 π^{\pm}$ decays basing on the factorization-assisted topological-amplitude (FAT) approach and the topological amplitude (TA) approach of Cheng and Chiang [Phys. Rev. D 104, 073003 (2021).]. We find that the CP violations in these decays $A_{CP}^{K_{S,L}^0}$ can exceed the order of $10^{-3}$ in the two approaches and consist of three parts: the indirect CP violations in $K^0 -\bar{K}^0$ mixing $A_{CP,K_{S,L}^0}^{mix}$, the direct CP violations in charm decays $A_{CP,K_{S,L}^0}^{dir}$ and the new CP violation effects $A_{CP,K_{S,L}^0}^{int}$, which are induced from the interference between two tree (Cabibbo-favored and doubly Cabibbo-suppressed) amplitudes with the neutral kaon mixing. The indirect CP violations in $K^0 -\bar{K}^0$ mixing play a dominant role in $A_{CP}^{K_{S,L}^0}$, the new CP violation effects have a non-negligible contribution to $A_{CP}^{K_{S,L}^0}$. We estimate the numerical results of the $K_S^0-K_L^0$ asymmetries $R_{K_{S}-K_{L}}^{D^{\pm}}$ and find that there exist a large difference between the numerical results in the FAT approach and that of the TA approach. We also find that if ones adopt the values of the decay time parameters $t_0 = 3.0 τ_S$ and $t_1 = 10.0 τ_S$, the new CP violation effect $A_{CP,K_{S}^0}^{int}$ would dominate the CP violation in $D^{\pm} \rightarrow K^{\ast}(892)^{0} π^{\pm} + \bar{K}^{\ast }(892)^{0}π^{\pm}\rightarrow K_{S}^0π^0 π^{\pm}$ decays and could be observed with $6.7\times 10^{6}$ and $6.5\times 10^{6}$ $D^{\pm}$ events-times-efficiency in the FAT approach and the TA approach, respectively. Our results could be tested by the LHCb, Belle II and BESIII experiments.

hep-ph↗

arXiv2022

Semileptonic $D$ Meson Decays $D\to P/V/S\ell^+ν_\ell$ with the SU(3) Flavor Symmetry/Breaking

Many exclusive $c\to d/s\ell^+ν_\ell~(\ell=e,μ,τ)$ transitions have been well measured, and they can be used to test the theoretical calculations. Motivated by this, we study the $D\to P/V/S\ell^+ν_\ell$ decays induced by the $c\to d/s\ell^+ν_\ell$ transitions with the SU(3) flavor symmetry approach, where $P$ denotes the pseudoscalar meson, $V$ denotes the vector meson, and $S$ denotes the scalar meson with a mass below $1$ $GeV$. The different decay amplitudes of the $D\to P\ell^+ν_\ell$, $D\to V\ell^+ν_\ell$ or $D\to S\ell^+ν_\ell$ decays can be related by using the SU(3) flavor symmetry and by considering the SU(3) flavor breaking. Using the present data of $D\to P/V/S\ell^+ν_\ell$, we predict the not yet measured or not yet well measured processes in the $D\to P/V/S\ell^+ν_\ell$ decays. We find that the SU(3) flavor symmetry approach works well in the semileptonic $D \to P/V\ell^+ν_\ell$ decays. For the $D \to S\ell^+ν_\ell$ decays, only the decay $D^+_s\to f_0(980)e^+ν_e$ has been measured, the branching ratios of the $D^+_s\to f_0(980)e^+ν_e$ and $D\to S(S\to P_1P_2)\ell^+ν_\ell$ decays are used to constrain the nonperturbative parameters and then predict not yet measured $D \to S\ell^+ν_\ell$ decays, in addition, the two quark and the four quark scenarios for the light scalar mesons are analyzed. The SU(3) flavor symmetry predictions of the $D \to S\ell^+ν_\ell$ decays need to be further tested, and our predictions of the $D \to S\ell^+ν_\ell$ decays are useful for probing the structure of light scalar mesons. Our results in this work could be used to test the SU(3) flavor symmetry approach in the semileptonic $D$ decays by the future experiments at BESIII, LHCb and BelleII.

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arXiv2021

Study of CP violation and CPT violation in $K^{\ast}(892)\rightarrow K_{S,L}^{0}π$ decays at BESIII

The decays $K^{\ast}(892)\rightarrow K_{S,L}^{0}π$ can be used to study CP violation and CPT violation. The $K^{\ast}(892)$ (hereinafter referred to as $K^{\ast}$) meson can be produced via $J/ψ$ decays at BESIII. In this paper, we study CP violation and $K_S^0-K_L^0$ asymmetry in the $J/ψ$ decays involving the $K^{\ast}$ meson in the final states and obtain the following results \begin{align} {\mathcal A}_{CP}\left(J/ψ\rightarrow K^{\ast}f_{J/ψ}\rightarrow K^0_{S}πf_{J/ψ}\right)=\left(3.64\pm0.04\right)\times 10^{-3},\nonumber\\ {\mathcal A}_{CP}\left(J/ψ\rightarrow K^{\ast}f_{J/ψ}\rightarrow K^0_{L}πf_{J/ψ}\right)=\left(-3.32\pm0.04\right)\times 10^{-3},\nonumber \end{align} and \begin{align} &R\left(J/ψ\rightarrow K^{\ast}f_{J/ψ}\rightarrow K^0_{S,L}πf_{J/ψ} \right)=\left(3.51\pm0.03\right)\times 10^{-3},\nonumber\\ &R\left(J/ψ\rightarrow \bar{K}^{\ast} \bar{f}_{J/ψ}\rightarrow K^0_{S,L}π\bar{f}_{J/ψ} \right)=\left(-3.45\pm0.03\right)\times 10^{-3}.\nonumber \end{align} Basing on two cases: the samples of $10^{10}$ and $10^{12}$ $J/ψ$ events, we calculate the expected numbers of the observed signal events on the CP violation and the $K_S^0-K_L^0$ asymmetry in the $J/ψ$ decays with $K^{\ast}$ meson in the final states, we find that the BESIII experiment may be able to unambiguously observe CP violation and $K_S^0-K_L^0$ asymmetry for each of these two cases. We study the possibility to constraint the CPT violation parameter $z$ and discuss the sensitivity for the measurement of $z$ in $J/ψ$ decays with $K^{\ast}$ meson in the final states at BESIII. The sensitivity of the measurement of $z$ depend on the measured precision of the parameters $m_L-m_S$, $Γ_L$, $Γ_S$, $p$ and $q$ and the consistence between the values of $t_0$ and $t_1$ and the event selection criteria in experiment.

hep-ph↗

arXiv2021

Effect of $K^0-\bar{K}^0$ Mixing on CP and CPT Violations in $B_{c}^{\pm}\rightarrow B^{\pm} K_{S,L}^{0}$ Decays

The large data sample of the $B_c$ meson collected at the LHC experiment and the HL-LHC experiment provides us the opportunity to study the $B_c$ decays and the related physics. In this paper, we investigate the effect of $K^0-\bar{K}^0$ mixing on the the branching ratios, CP violations and CPT violations in the $B_{c}^{\pm}\rightarrow B^{\pm} K_{S,L}^{0}$ decays. We find that some of the $B_c^{\pm}\rightarrow B^{\pm} K_{S,L}^0\rightarrow f_{B^{\pm}} f_{K_{S,L}^0}$ decay chains have large branching ratios, whose maximum value can exceed the order of $10^{-6}$, the minimum number of $B_c^\pm$ events times efficiency for observing the decays at three standard deviations (3$σ$) level is about $ 10^6$. We study the CP asymmetries in the $B_c^{\pm}\rightarrow B^{\pm} K_{S,L}^0$ decays and find that the CP asymmetries can exceed the order of $10^{-3}$, which are dominated by $K^0-\bar{K}^0$ mixing. We give the most promising processes to observe the CP violations and the ranges of the numbers of $B_c^\pm$ events-times-efficiency needed to observe the CP asymmetries at a significance of 3$σ$ in these decays. We investigate the possibility to constraint the CPT violation parameter $z$ in the $B_c^{\pm}\rightarrow B^{\pm} K_{S,L}^0\rightarrow f_{B^{\pm}} f_{K_{S,L}^0}$ decays and give the most promising processes to constraint the parameter $z$.

hep-ph↗

arXiv2021

Studying $\mathcal{B}_1(\frac{1}{2}^+)\to \mathcal{B}_2(\frac{1}{2}^+)\ell^+\ell^-$ Semi-leptonic Weak Baryon Decays with the SU(3) Flavor Symmetry

Motivated by recent anomalies in FCNC $b\to s\ell^+\ell^-$, we study $B_1\to B_2\ell^+\ell^-(\ell=e,μ,τ)$ semi-leptonic weak decays with the SU(3) flavor symmetry, where $B_{1,2}$ are the spin-1/2 baryons of single bottomed anti-triplet $T_{b3}$, single charmed anti-triplet $T_{c3}$ or light baryon octet $T_{8}$. Using the SU(3) irreducible representation approach, we first obtain the amplitude relations among different decays, and then predict the relevant not-yet measured observables of these decays. (a) We calculate the branching ratios of the $T_{b3}\to T_8 μ^+μ^-$ and $T_{b3}\to T_8 τ^+τ^-$ in the whole $q^2$ region and in the different $q^2$ bins by the measurement of $Λ^0_b\to Λ^0 μ^+μ^-$. Many of them are obtained for the first time. In addition, the longitudinal polarization fractions and the leptonic forward-backward asymmetries of all $T_{b3}\to T_{8}\ell^+\ell^-$ decays are very similar to each other in certain $q^2$ bin due to the SU(3) flavor symmetry. (b) We analyze the upper limits of $B(T_{c3}\to T_{8}\ell^+\ell^-)$ by using the experimental upper limits of $B(Λ^+_c\to pμ^+μ^-)$ and $B(Λ^+_c\to pe^+e^-)$, and find the experimental upper limit of $B(Λ^+_c\to pμ^+μ^-)$ giving effective bounds on the relevant SU(3) flavor symmetry parameters. The predictions of $B(Ξ^0_c \to Ξ^0e^+e^-)$ and $B(Ξ^0_c \to Ξ^0μ^+μ^-)$ will be different between the single-quark transition dominant contributions and the W-exchange dominant ones. (c) As for $T_{8}\to T'_8 \ell^+\ell^-$ decays, we analyze the single-quark transition contributions and the W-exchange contributions by using two measurements of $ B(Ξ^0\to Λ^0 e^+e^-)$ and $ B(Σ^+\to pμ^+μ^-)$, and give the branching ratio predictions by assuming either single-quark transition dominant contributions or the W-exchange dominant ones.

hep-ph↗

arXiv2020

Probing new physics in semileptonic $Σ_b$ and $Ω_b$ decays

Recently, several hints of lepton non-universality have been observed in the semileptonic B meson decays in terms of both in the neutral current ($b\to s l \bar{l}$) and charged current ($b\to c l \bar{ν_{l}}$) transitions. Motivated by these inspiring results, we perform the analysis of the baryon decays ${Σ_b}\to Σ_c l \bar{ν_{l}}$ and $Ω_b\to Ω_c l \bar{ν_{l}} (l=e,μ,τ)$ which are mediated by $ b \to c l \bar{ν_{l}}$ transitions at the quark level, to scrutinize the nature of new physics (NP) in the model independent method. We first use the experimental measurements of $\mathcal{B}( B\to D^{(*)} l\bar{ν_{l}})$, ${\rm R}_{D^{(*)}}$ and ${\rm R}_{J/ψ}$ to constrain the NP coupling parameters in a variety of scenarios. Using the constrained NP coupling parameters, we report numerical results on various observables related to the processes ${Σ_b}\to Σ_c l \bar{ν_{l}}$ and $Ω_b\to Ω_c l \bar{ν_{l}}$, such as the branching ratios, the ratio of branching fractions, the lepton side forward-backward asymmetries, the hadron and lepton longitudinal polarization asymmetries and the convexity parameter. We also provide the $q^2$ dependency of these observables and we hope that the corresponding numerical results in this work will be testified by future experiments.

hep-ph↗

arXiv2020

Studying Radiative Baryon Decays with the SU(3) Flavor Symmetry

The weak and electromagnetic radiative baryon decays of octet $T_{8}$, decuplet $T_{10}$, single charmed anti-triplet $T_{c3}$ and sextet $T_{c6}$, single heavy bottomed anti-triplet $T_{b3}$ and sextet $T_{b6}$ are investigated by using SU(3) flavor symmetry irreducible representation approach. We analyze the contributions from a single quark transition $q_1\to q_2γ$ and $W$ exchange transitions, and find that the amplitudes could be easily related by SU(3) flavor symmetry in the $T_{b3,b6}$ weak radiative decays, $T_{c3,c6}$ weak radiative decays, $T_{10}\to T_{8}γ$ weak decays, $T_{10}\to T'_{10}γ$ weak decays and $T_{10}\to T_{8}γ$ electromagnetic decays. Nevertheless, the amplitude relations are a little complex in the $T_{8}\to T'_{8}γ$ and $T_{8}\to T_{10}γ$ weak decays due to quark antisymmetry in $T_{8}$ and $W$ exchange contributions. Predictions for branching ratios of $Λ^{0}_b\to nγ$, $Ξ^{-}_b\to Ξ^-γ$, $Ξ^{-}_b\to Σ^-γ$, $Ξ^{0}_b\to Σ^0γ$, $Ξ^{0}_b\to Λ^0γ$, $Ξ^{0}_b\to Ξ^0γ$, $Ξ^{*}\to Ξγ$, $Σ^{*0}\to Σ^{0}γ$, $Δ^0\to nγ$ and $Δ^+\to pγ$ are given. The results in this work can be used to test SU(3) flavor symmetry approach in the radiative baryon decays by the future experiments at BESIII, LHCb and Belle-II.

hep-ph↗

arXiv2020

Studying Two-body Nonleptonic Weak Decays of Hyperons with Topological Diagram Approach

Many decays of light baryons consisting of light $u,d,s$ quarks have been measured, and these measurements will help us to understand the decay properties of light baryons. In this work, we study two-body nonleptonic weak decays of light baryon octet $(T_8)$ and baryon decuplet $(T_{10})$ by the topological diagram approach (TDA) under the SU(3) flavor symmetry for the first time. We find that (1) the TDA and the SU(3) irreducible representation approach (IRA) match consistently in $T_{10}\to T^{(')}_{8,10}P_8$ ($P_8$ is the light pseudoscalar meson octet); (2) almost all relevant not-yet-measured $\mathcal{B}(T_{10}\to T_8 P_8)$ may be predicted by using three experimental data of $\mathcal{B}(Ω^-\to Ξ^0π^-,Ξ^-π^0,Λ^0K^-)$, and the upper limits of $\mathcal{B}(T_{10}\to T{'}_{10}π^-)$ may be obtained from the experimental upper limit of $\mathcal{B}(Ω^-\to Ξ^{*0}π^-)$ by both the TDA and the IRA together, nevertheless, all new predicted branching ratios are too small to br reached in current experiments; (3) $T_8\to T'_8 P_8$ decays are quite complex in terms of the TDA, and we find that W-exchange diagrams give large and even dominant contributions by using relevant experimental data and the isospin relations.

hep-ph↗

arXiv2020

Study of $a_0^0(980)$-$f_0(980)$ mixing from $a_0(1450) \to a_0^0(980) f_0(500) \to π^+ π^- f_0(500)$

The $a_0^0(980)-f_0(980)$ mixing is one of the most potential tools to learn about the nature of $a_0^0(980)$ and $f_0(980)$. Using the $f_0(980)$-$a_0^0(980)$ mixing intensity $ξ_{af}$ measured recently at BESIII, we calculate the the branching ratio of the the isospin violation decay $J/ψ\rightarrowγη_c \rightarrow γπ^0 a_0^0(1450)\rightarrow γπ^0 a_0^0(980)f_0(500)\rightarrow γπ^0 f_0(980) f_0(500) \rightarrow γπ^0 π^+π^- π^+π^-$. The value of the branching ratio is found to be $O(10^{-6})$, which can be observed with $10^{10}$ $J/ψ$ events collected at BESIII. The narrow peak from the $f_0(980)$-$a_0^0(980)$ mixing in the $π^+π^-$ mass square spectrum can also be observed. In addition, we study the non-resonant decay $a_0^0(1450)\rightarrow f_0(980) π^+π^-(\text{non-resonant})$, which is dominated by the $a_0^0(980)$-$f_{0}(980)$ mixing. We find that the non-resonant decay $a_0^0(1450)\rightarrow f_0(980) π^+π^-$ and the decay $a_0^0(1450)\rightarrow f_0(980) f_0(500)$ can be combined to measure the mixing intensity $ξ_{af}$ in experiment. These decays are the perfect complement to the decay $χ_{c1}\rightarrow f_{0}(980)π^{0}\toπ^{+}π^{-}π^{0}$ which had been observed at BESIII, the observations of them will make the measurement of the mixing intensity $ξ_{af}$ more precisely.

hep-ph↗