论文标题
矢量leptoquarks超越树级III：矢量般的费米和改变风味的过渡
Vector Leptoquarks Beyond Tree Level III: Vector-like Fermions and Flavor-Changing Transitions
论文作者
论文摘要
在该主题上扩展了以前的工作，我们评估了在$ su（4）\ times su（3）^\ prime \ prime \ prime \ times su（2）_l \ times _x u（1）_x $ u（1）_x $ GAUGUGE组中，嵌入了大量矢量leptokark的模型中，以近来领先的订单准确性评估了类似向量的费米子的影响。类似矢量的fermions引起了新的风味对称性破坏，从而导致该模型最小版本中不存在的leptoquark的树级变化的耦合。反过来，这些导致一系列不变风味的中性振幅在循环水平上。我们将这些效果系统地分析了半蛋白质，偶极子和$ΔF= 2 $运算符。详细讨论了这些更正在$ b \对sν$和$ b \对Cτν$可观察物的影响。特别是，我们表明，在参数区域为$ b $ - 物理异常提供良好的拟合度，该型号预测$ 10 \％$至$ 50 \％$ $ $增强$ \ Mathcal {b}（b \ to K^{（*）}ννNνν）$。
Extending previous work on this subject, we evaluate the impact of vector-like fermions at next-to-leading order accuracy in models with a massive vector leptoquark embedded in the $SU(4)\times SU(3)^\prime\times SU(2)_L\times U(1)_X$ gauge group. Vector-like fermions induce new sources of flavor symmetry breaking, resulting in tree-level flavor-changing couplings for the leptoquark not present in the minimal version of the model. These, in turn, lead to a series of non-vanishing flavor-changing neutral-current amplitudes at the loop level. We systematically analyze these effects in semileptonic, dipole and $ΔF=2$ operators. The impact of these corrections in $b\to sνν$ and $b\to cτν$ observables are discussed in detail. In particular, we show that, in the parameter region providing a good fit to the $B$-physics anomalies, the model predicts a $10\%$ to $50\%$ enhancement of $\mathcal{B}(B\to K^{(*)}νν)$.
