arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1012.4686hep-ex
收藏

一种新的共振衰减到di-tau的质量重建技术

A New Mass Reconstruction Technique for Resonances Decaying to di-tau

A. Elagin, P. Murat, A. Pranko, A. Safonov

备注：
added new section with CDF data results; submitted to Nucl. Instrum. Methods
发表信息：
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Volume 654, Issue 1, 21 October 2011, Pages 481-489
阅读 PDF
arXiv 页面 ↗HTML 原文 ↗

摘要：

精确重建共振衰变为一对$τ$轻子的质量具有挑战性，因为存在来自$τ$衰变的多个中微子。现有的方法依赖于一个部分重建的质量，它具有广泛的频谱，降低灵敏度，或共线近似，这是只适用于相对较小的一部分的事件。我们描述了一种新的技术，它提供了一个准确的质量重建的原始共振，并不遭受共线近似的限制。主要的改进来自于用中微子和其他衰变产物的相互取向与$τ$轻子的质量和衰变运动学相一致的要求取代了共线近似的假设。这是通过最小化运动学允许的相空间区域中定义的似然函数来实现的。在本文中，我们描述了该技术，并说明其性能使用$Z/γ^{*}\toττ$和$H\toττ$事件模拟与现实的探测器分辨率。该方法还测试了在Tevatron的CDF实验收集的数据$Z/γ^{*}\toττ$事件的干净样本。我们期望这项新技术能在大型强子对撞机和Tevatron上对希格斯玻色子的研究有重大的改进。

英文摘要：

Accurate reconstruction of the mass of a resonance decaying to a pair of $τ$ leptons is challenging because of the presence of multiple neutrinos from $τ$ decays. The existing methods rely on either a partially reconstructed mass, which has a broad spectrum that reduces sensitivity, or the collinear approximation, which is applicable only to the relatively small fraction of events. We describe a new technique, which provides an accurate mass reconstruction of the original resonance and does not suffer from the limitations of the collinear approximation. The major improvement comes from replacing assumptions of the collinear approximation by a requirement that mutual orientations of the neutrinos and other decay products are consistent with the mass and decay kinematics of a $τ$ lepton. This is achieved by minimizing a likelihood function defined in the kinematically allowed phase space region. In this paper we describe the technique and illustrate its performance using $Z/γ^{*}\toττ$ and $H\toττ$ events simulated with the realistic detector resolution. The method is also tested on a clean sample of data $Z/γ^{*}\toττ$ events collected by the CDF experiment at the Tevatron. We expect that this new technique will allow for a major improvement in searches for the Higgs boson at both the LHC and the Tevatron.

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。

↑