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arXiv 1102.4160hep-ph
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夸克-双夸克模型中$Σ_{b}, Λ_{b}$重子的光谱和衰变性质

Spectroscopy and decay properties of $Σ_{b}, Λ_{b}$ baryons in quark-diquark model

Ajay Majethiya, Kaushal Thakkar, P. C. Vinodkumar

摘要:

基于夸克-双夸克结构研究了单美重子($Σ_{b},Λ_{b}$)的性质。约束势被假定为两个体色库仑势加上指数为$ν$的幂势。我们发现重夸克质量参数($m_{b}$)、强耦合常数($α_{s}$)和势指数($ν$)的选择与$m_{Σ^{*}_{b}}- m_{Σ_{b}}=21.2\pm2.0 $ MeV的实验质量分裂有很强的相关性。用所得的谱参数计算了$Σ_{b}, Λ_{b}$系统的磁矩、电磁辐射衰变、强强子衰变和半轻子衰变宽度。我们对$Σ^{*0}_{b}\rightarrowΛ_{b}γ$对应的辐射衰变宽度的预言与QCD求和规则的预言是一致的。$Λ_{b}\rightarrow Λ_{c}lν_{l}$(2.50-4.73)$ *10^{10} s^{-1}$的半轻子衰变宽度与PDG(2010)报道的$3.59^{+1.234}_{-0.936} *10^{10} s^{-1}$的实验值一致。

英文摘要:

Properties of single beauty baryons ($Σ_{b},Λ_{b}$) are studied based on the quark-diquark structure. The confinement potential is assumed as two body colour coulomb plus power potential with exponent $ν$. We find a strong correlation between the choice of the heavy quark mass parameter ($m_{b}$), strong coupling constant ($α_{s}$) and the potential exponent ($ν$) for getting the experimental mass spilt of $m_{Σ^{*}_{b}}- m_{Σ_{b}}=21.2\pm2.0 $ MeV. The resultant spectroscopic parameters are used for computing magnetic moments, the electromagnetic radiative decay, strong hadronic decay and semileptonic decay widths of $Σ_{b}, Λ_{b}$ systems. Our predictions on the radiative decay width correspond to $Σ^{*0}_{b}\rightarrowΛ_{b}γ$ are in agreement with the QCD sum rule prediction. The present results on the semileptonic decay widths of $Λ_{b}\rightarrow Λ_{c}lν_{l}$ (2.50-4.73) $ *10^{10} s^{-1}$ are in agreement with the experimental value of $3.59^{+1.234}_{-0.936} *10^{10} s^{-1}$ reported by (PDG 2010).

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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