论文标题
$λ_b\toλ$ transitions的本地形态的分散界
Dispersive bounds for local form factors in $Λ_b \to Λ$ transitions
论文作者
论文摘要
我们调查了与$ b $ -baryon衰减相关的十个独立的本地形式因子$λ_b\ toλ\ ell^+\ ell^ - $，结合了晶格QCD和分散范围的信息。我们提出了形式因素的新型参数化，以正规的多项式为角度，将形状因子对分散界的贡献贡献。这是针对中膜到膜形式因子开发的单位性界限的概括。与这些形式因素的临时参数化相反，我们的参数化提供了一定程度的控制形式因子不确定性，在大的耐药后坐力下。对于$λ_b\toλγ$和$λ_b\toλ\ ell^+el^+el^ - $衰减过程的理论预测，这是现象学的兴趣。
We investigate the ten independent local form-factors relevant to the $b$-baryon decay $Λ_b \to Λ\ell^+\ell^-$, combining information of lattice QCD and dispersive bounds. We propose a novel parametrization of the form factors in terms of orthonormal polynomials that diagonalizes the form factor contributions to the dispersive bounds. This is a generalization of the unitarity bounds developed for meson-to-meson form-factors. In contrast to ad-hoc parametrizations of these form factors, our parametrization provides a degree of control of the form-factor uncertainties at large hadronic recoil. This is of phenomenological interest for theoretical predictions of, e.g., $Λ_b\to Λγ$ and $Λ_b\toΛ\ell^+\ell^-$ decay processes.
