Jet pull is an observable designed to probe colour flow between jets. Thus far, a particular projection of the pull vector, the pull angle, has been employed to distinguish colour flow between jets produced by a colour singlet or an octet decay. This is of particular importance in order to separate the decay of a Higgs boson to a pair of bottom quarks from the QCD background. However, the pull angle is not infra-red and collinear (IRC) safe. In this paper we introduce IRC safe projections of the pull vector that exhibit good sensitivity to colour flow, while maintaining calculability. We calculate these distributions to next-to- leading logarithmic accuracy, in the context of the hadronic decay of a Higgs boson, and compare these results to Monte Carlo simulations. This study allows us to define an IRC safe version of the pull angle in terms of asymmetry distributions. Furthermore, because of their sensitivity to wide-angle soft radiation, we anticipate that these asymmetries can play an important role in assessing subleading colour correlations and their modelling in general-purpose Monte Carlo parton showers.

中文翻译：

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喷射拉力的安全使用

射流拉力是一种可观察的，旨在探测射流之间的颜色流动。到目前为止，拉力矢量的特定投影，拉力角，已被用于区分由颜色单线态或八位位组衰减产生的射流之间的颜色流。这对于将希格斯玻色子衰变成一对底夸克与 QCD 背景分离尤为重要。然而，牵引角不是红外线和共线 (IRC) 安全的。在本文中，我们介绍了拉力矢量的 IRC 安全投影，它对颜色流表现出良好的敏感性，同时保持可计算性。我们在希格斯玻色子的强子衰变的背景下，以次领先的对数精度计算这些分布，并将这些结果与蒙特卡罗模拟进行比较。这项研究使我们能够根据不对称分布定义拉力角的 IRC 安全版本。此外，由于它们对广角软辐射的敏感性，我们预计这些不对称性可以在评估次领先的颜色相关性及其在通用蒙特卡罗帕顿阵雨中的建模方面发挥重要作用。