论文标题
$λ_b\toλ^*_ j（pk^ - ）j/ψ$衰减的角度分布
Angular distributions for $Λ_b\to Λ^*_J (pK^-)J/ψ$ Decays
论文作者
论文摘要
我们对多体衰减级联$λ_b\ toλ^*_ j j j/ψ\ to pk^ - j/ψ$进行分析，并与$λ^*_ j $共振，包括$λ^*_ {1520}，λ^*_ {1520}，λ^*_ {1600} $，$ j Rec/$ j Rec/$ lip orec y $ liet urec，以及$λ^*_} Lepton对最终状态。使用螺旋度振幅技术，我们为衰减链的角度分布提供了一种紧凑的形式，从中可以提取各种一维分布。使用$λ_b\ toλ_j^*$从晶格QCD和Quark模型中进行表格，我们计算差分和集成的部分宽度。衰减分支分数被发现为$ \ MATHCAL {b}（λ_b\toλ^*_ j（pk）j/ψ（\ ell^+\ ell^ - ））=（1.35 \ pm0.28）\ times 10^{ - 5} $。此外，我们还探索前后不对称和各种极化。这项工作中的结果将对$ b \ to s \ ell^+\ ell^ - $ n-λ_b$衰减的研究进行校准。
We carry out an analysis of the multibody decay cascade $Λ_b\to Λ^*_J J/ψ\to pK^- J/ψ$ with the $ Λ^*_J$ resonance including $Λ^*_{1520},Λ^*_{1600}$, and $Λ^*_{1800}$, and $J/ψ$ reconstructed by the lepton pair final state. Using the helicity amplitude technique, we derive a compact form for the angular distributions for the decay chain, from which one can extract various one-dimensional distributions. Using the $Λ_b\to Λ_J^*$ form factors from lattice QCD and quark model, we calculate the differential and integrated partial widths. Decay branching fractions are found as $\mathcal{B}(Λ_b\to Λ^*_J( pK)J/ψ(\ell^+\ell^-))=(1.35\pm0.28)\times 10^{-5}$. In addition, we also explore forward-backward asymmetry, and various polarizations. Results in this work will serve a calibration for the study of $b\to s \ell^+\ell^-$ decays in $Λ_b$ decays in future and provide useful information towards the understanding of the properties of the $Λ_J^*$ baryons.
