论文标题
$λ_b\toλ^\ ast（1520）（\ to n \！\ bar {k}）\ ell^+\ ell^ - $ decay在HQET中的低recoil
The $Λ_b\toΛ^\ast(1520)(\to N\!\bar{K})\ell^+\ell^-$ decay at low-recoil in HQET
论文作者
论文摘要
在本文中，我们讨论了$λ_b\toλ^\ ast（1520）（\ to N \！ n \ bar {k}^0 \} $。我们为包括标准型号运算符及其手性翻转的手性的一组操作员提供了完整的角度分布，以及新的标量和伪量表操作员。所得的角度分布使我们能够在标准模型和独立于模型的新物理方案中构造我们研究的可观察物。为了减少从$λ_b\toλ^\ ast（1520）$过渡形式的辐射效应，我们利用了在低$ $λ^\ ast（1520）$后退的重量夸克有效理论框架，\ emph {i.e.e。e.e。以$ 1/m_b $的价格为领先顺序工作，包括$ \ Mathcal {o}（α_s）$校正，我们计算形式之间的“改善的iSgur-wise关系”。该关系将形式因素关联，从而使低重生区域的这种衰变与较少数量的独立形式的描述。
In this paper we discuss the Standard Model and new physics sensitivity of the $Λ_b\toΛ^\ast(1520)(\to N\!\bar{K})\ell^+\ell^-$ decay at low-recoil, where $\ell^\pm$ are massive leptons and $N\!\bar{K}=\{pK^-, n\bar{K}^0 \}$. We provide a full angular distribution with a set of operators that includes the Standard Model operators and their chirality flipped counterparts, and new scalar and pseudo-scalar operators. The resulting angular distribution allows us to construct observables that we study in the Standard Model and in model-independent new physics scenarios. To reduce the hadronic effects emanating from the $Λ_b\toΛ^\ast(1520)$ transition form factors, we exploit the Heavy Quark Effective theory framework valid at low $Λ^\ast(1520)$ recoil, \emph{i.e.,} large dilepton invariant mass squared $q^2\sim \mathcal{O}(m_b^2)$. Working to the leading order in $1/m_b$ and including $\mathcal{O}(α_s)$ corrections, we compute the `improved Isgur-Wise relations' between the form factors. The relations correlate the form factors and thereby allow the description of this decay at the low-recoil region with a smaller number of independent form factors.
