论文标题
介子中的隆隆声：leptoquark ves a $ z^\ prime $适合$ b \ rightarrowsμ^+μ^ - $ $异常，包括2022 lhcb $ r_ {k^{（\ ast）}} $测量值
The Rumble in the Meson: a leptoquark versus a $Z^\prime$ to fit $b \rightarrow s μ^+ μ^-$ anomalies including 2022 LHCb $R_{K^{(\ast)}}$ measurements
论文作者
论文摘要
我们将两种自下而上的模型（$ s_3 $标量leptoark型号和$ {b_3-l_2} $ $ z^\ prime $型号）与\ bsll \ andolies的$ {b_3-l_2} $ {b_3-l_2} $ {b_3-l_2} $ {bsll \ prime $型号）并列，以调味数据，以量化统计偏好或缺乏。 Leptoquark模型直接伴侣与左手的二线对，而$ z^\ prime $型号的模型与Di-Muon对与矢量般的耦合。 $ b_s- \ overline {b_s} $混合是一个焦点，因为通常期望它会使$ z^\ prime $解释。在两参数中符合247个风味可观察物，包括$ b_ {s/d} \至μ^+μ^ - $分支比例，我们提供更新的组合和LHCB $ r_ {k^{（\ ast）}} $测量值，我们显示每种模型从2022年12月显示，我们显示出类似的改进质量效果。相对于标准模型，$ \ sqrt {Δχ^2} = 3.6 $。 $ b_s- \ overline {b_s} $混合约束的主要效果是，$ s^\ prime $模型在disfavour valuep中的$ s_l-b_l $混合角度大于$ 5 | v_ v_ {cb} | $。此限制相当松，这意味着在Quark Yukawa Matrix中，良好的数据不需要“对齐”。 $ S_3 $模型中没有明显的限制$ S_L-B_L $混合角度。
We juxtapose global fits of two bottom-up models (an $S_3$ scalar leptoquark model and a ${B_3-L_2}$ $Z^\prime$ model) of \bsll\ anomalies to flavour data in order to quantify statistical preference or lack thereof. The leptoquark model couples directly to left-handed di-muon pairs, whereas the $Z^\prime$ model couples to di-muon pairs with a vector-like coupling. $B_s-\overline{B_s}$ mixing is a focus because it is typically expected to disfavour $Z^\prime$ explanations. In two-parameter fits to 247 flavour observables, including $B_{s/d} \to μ^+ μ^-$ branching ratios for which we provide an updated combination and LHCb $R_{K^{(\ast)}}$ measurements from December 2022, we show that each model provides a similar improvement in quality-of-fit of $\sqrt{Δχ^2}=3.6$ with respect to the Standard Model. The main effect of the $B_s-\overline{B_s}$ mixing constraint in the $Z^\prime$ model is to disfavour values of the $s_L-b_L$ mixing angle greater than about $5|V_{cb}|$. This limit is rather loose, meaning that a good fit to data does not require `alignment' in either quark Yukawa matrix. No curtailment of the $s_L-b_L$ mixing angle is evident in the $S_3$ model.
