Improved measurement of the neutral pion decay into electron, positron and photon, and optimisation of the kaon tagger using hydrogen in NA62.

改进了中性π介子衰变成电子、正电子和光子的测量，并在 NA62 中使用氢优化了 kaon 标记器。

• 批准号: 2128979
• 金额: --
• 依托单位: University of Birmingham
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2018
• 资助国家: 英国
• 起止时间: 2018 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2128979
• 关键词: Improved; measurement; neutral; pion; decay

My research will be carried out as part of the NA62 experiment at CERN. NA62 is a fixed target experiment and is designed to measure rare decays of kaons and pions. It's main aim is to obtain a 10% measurement of the Vtd CKM parameter. A large number of detectors are required to provide the necessary particle identification, high-resolution timing, kinematic rejection and hermetic vetoing of photons. The NA62 experiment uses a Cherenkov detector (known as KTAG) which identifies kaons and pions by detecting the Cherenkov light emitted. The KTAG uses a CEDAR vessel which is filled with nitrogen gas and contains several optical instruments which are finely tuned so that the Cherenkov light emitted by the particles is focused to sets of photomultiplier tubes upstream of the CEDAR. For the initial stage of my research, I will be investigating whether the current optics can be adapted so that instead of using nitrogen gas, hydrogen could be used. This would have the advantage of reducing the multiple scattering of the kaons travelling through the detector. The main part of my research project will be working on an improvement in the single Dalitz decay branching fraction. The current branching fraction measurement of the single Dalitz decay is (1.174 +/- 0.035)%. The aim of my project will be to improve this from a 3% to a 1% measurement.

我的研究将作为欧洲核子研究中心NA62实验的一部分进行。NA62是一项固定目标实验，旨在测量介子和介子的罕见衰变。它的主要目的是获得VTD CKM参数的10%的测量结果。需要大量的探测器来提供必要的粒子识别、高分辨率计时、运动学拒绝和封闭的光子否决。NA62实验使用切伦科夫探测器(称为KTAG)，它通过探测发出的切伦科夫光来识别介子和介子。KTAG使用一个塞满氮气的雪松容器，其中包含几个经过微调的光学仪器，以便粒子发射的切伦科夫光聚焦到雪松上游的几组光电倍增管上。在我的研究的初始阶段，我将调查是否可以调整目前的光学系统，以取代使用氮气，而使用氢气。这将具有减少穿过探测器的介子的多次散射的优点。我的研究项目的主要部分将致力于改进单个Dalitz衰变分支分数。目前测量的单个Dalitz衰变的分枝分数为(1.174+/-0.035)%。我的项目的目标是将这一比例从3%提高到1%。