论文标题
$λ_b\ toλ_cτν$测量对$ b \ to c \，lν$ transions的影响
Impact of $Λ_b\to Λ_cτν$ measurement on New Physics in $b\to c \, l ν$ transitions
论文作者
论文摘要
分支比的分支比的测量值为$ b \ d^{（*）}τ\barν/b \ d^{（*）} \ ell \barν$和$ b_c \ b_c \ to j/ψ\，τ\ barv \barν/b_c \ to j/b_c \ to j/b to j/n \ bab bab bab bab bab bab lhar and lhar and lhar and lhar and lhar and lhar and lhar，与带有轻质的通道相比。但是，比率$λ_b\toλ_cτ\barν/λ_b\toλ_c\ ell \barν$在taus中表现出相对赤字。在本文中，我们批判性地解决了数据是否仍然指向连贯的偏差模式，尤其是鉴于以模型无关的方式与这些衰减相关的总规则。我们发现，没有对所有比率的常见新物理解释（在$2σ$或$1.5σ$之内，具体取决于$ {\ cal r}（λ_c）$归一化到光Lepton通道）。虽然这种不一致可能是统计波动，但需要进一步的测量以收敛到实验结果的连贯模式。
Measurements of the branching ratios of $B \to D^{(*)}τ\barν/B \to D^{(*)}\ell\barν$ and $B_c\to J/ψ\, τ\barν/B_c\to J/ψ\, \ell\barν$ by the BaBar, Belle and LHCb collaborations consistently point towards an abundance of taus compared to channels with light leptons. However, the ratio $Λ_b \toΛ_c τ\barν/Λ_b \toΛ_c \ell\barν$ shows a relative deficit in taus. In this paper, we critically address whether data still points towards a coherent pattern of deviations, in particular in light of the sum rule relating these decays in a model-independent way. We find that no common new physics explanation of all ratios is possible (within $2σ$ or $1.5σ$, depending on the ${\cal R}(Λ_c)$ normalization to light lepton channels). While this inconsistency could be a statistical fluctuation, further measurements are required in order to converge to a coherent pattern of experimental results.
