arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1402.2657hep-ph
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软跌落

Soft Drop

Andrew J. Larkoski, Simone Marzani, Gregory Soyez, Jesse Thaler

摘要:

我们介绍了一种新的射流子结构技术,称为“软滴declustering”,递归地删除软广角辐射从射流。软下降算法取决于两个参数-软阈值$z_\text{cut}$和角度指数$β$ -其中$β= 0$极限大致对应于(修改的)质量下降过程。为了获得一个分析的理解,软滴和突出的$β$的依赖,我们执行三个观测值的软滴射流:能量关联函数,梳理射流半径,和由于软滴的能量损失的计算。能量损失的$β= 0$极限是特别有趣的,因为它不仅是“Sudakov安全的”,而且在很大程度上对强耦合常数的值不敏感。虽然我们的计算是严格准确的,只有修改的领先对数的顺序,我们还包括一个更高阶的影响,如多个排放和(的情况下)的非全球性的讨论。我们比较我们的分析结果部分子淋浴模拟,并找到很好的协议,我们还估计了非微扰效应,如强子化和潜在的事件的影响。最后,我们演示了如何软降可用于标记提升W玻色子,我们推测使用软降堆积缓解的潜在优势。

英文摘要:

We introduce a new jet substructure technique called "soft drop declustering", which recursively removes soft wide-angle radiation from a jet. The soft drop algorithm depends on two parameters--a soft threshold $z_\text{cut}$ and an angular exponent $β$--with the $β= 0$ limit corresponding roughly to the (modified) mass drop procedure. To gain an analytic understanding of soft drop and highlight the $β$ dependence, we perform resummed calculations for three observables on soft-dropped jets: the energy correlation functions, the groomed jet radius, and the energy loss due to soft drop. The $β= 0$ limit of the energy loss is particularly interesting, since it is not only "Sudakov safe" but also largely insensitive to the value of the strong coupling constant. While our calculations are strictly accurate only to modified leading-logarithmic order, we also include a discussion of higher-order effects such as multiple emissions and (the absence of) non-global logarithms. We compare our analytic results to parton shower simulations and find good agreement, and we also estimate the impact of non-perturbative effects such as hadronization and the underlying event. Finally, we demonstrate how soft drop can be used for tagging boosted W bosons, and we speculate on the potential advantages of using soft drop for pileup mitigation.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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