Partial wave analysis of events in proton-proton reactions for energies between 1.9 and 3.5 GeV

1.9 至 3.5 GeV 能量的质子-质子反应事件的部分波分析

• 批准号: 258435442
• 负责人: Professorin Dr. Laura Fabbietti
• 金额: --
• 依托单位: Arbeitsgruppe Dichte und seltsame hadronische Materie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2023-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/258435442?language=en
• 关键词: Partial; wave; analysis; events; proton

The spectrum and the properties of nucleon resonances provide important insight into the non-perturbative sector of QCD. A proper way to investigate these nucleon resonances is to use a Partial-Wave-Analysis (PWA), where experimental data are decomposed into a sum of different partial wave amplitudes. For this purpose, mainly data on pion Nucleon elastic and inelastic reactions were considered in the past. Recently, it became also possible to study p+p reactions, where especially the production of open strangeness via the reaction p+p (to) p+ Lambda + K attracts a lot of interest. These reactions can indeed deliver new and complementary insight into the spectrum of N(star) resonances with a significant coupling to the Lambda Kaon decay channel. Furthermore, data on the p KLambda final state are extremely interesting in the context of strange exotic particles, like the predicted ppK.The study of the existence and the properties of such states in p+p reactions can contribute to an improved understanding of the low energy anti kaon nucleon dynamics below threshold. In herewith proposed project we intend to investigate various existing data on pKLambda production at different energies, and aim to fit all these data simultaneously with the Bonn-Gatchina PWA program. For this purpose, we will first apply the PWA to each data set separately, so that we get a first evaluation of which N(star) resonances contribute at which energy. Afterwards, we will combine all the data sets and fit them simultaneously. In this way we can extract the energy dependence for the different partial wave amplitudes. Finally, we also want to implement a ppK wave in the PWA framework, so that we can test how much room the data leave for the existence of such an exotic state.The results of the proposed analysis will contribute to an improved understanding of the N(star) resonance spectrum and it will also help to solve the puzzle about the existence or non-existence of kaonic-nuclear clusters, where the ppK is only the is only the simplest representation. The project shall be topic of a two and a half years Post Doc position.

核子共振的光谱和性质提供了对QCD非微扰部分的重要认识。研究这些核子共振的一个适当方法是使用分波分析（PWA），其中实验数据被分解为不同分波振幅的总和。为此目的，过去主要考虑π介子核子弹性和非弹性反应的数据。最近，研究p+p反应也成为可能，特别是通过反应p+p（to）p+ Lambda + K产生开放奇异性吸引了很多兴趣。这些反应确实可以提供新的和互补的洞察频谱的N（星星）共振与显着耦合的λ K介子衰变通道。此外，p K λ末态的数据是非常有趣的背景下，奇怪的外来粒子，如预测的ppK.在p+p反应中的存在和这种状态的性质的研究，可以有助于提高理解的低能量反K介子核子动力学低于阈值。在此提出的项目中，我们打算调查不同能量下pKLambda生产的各种现有数据，并旨在同时将所有这些数据与Bonn-Gatchina PWA计划相匹配。为此，我们将首先将PWA分别应用于每个数据集，以便我们首先评估哪些N（星星）共振在哪些能量下起作用。然后，我们将联合收割机组合所有数据集并同时拟合它们。通过这种方式，我们可以提取不同分波振幅的能量依赖性。最后，我们还想在PWA框架下实现一个ppK波，这样我们就可以测试数据为这种奇异态的存在留下了多大的空间。所提出的分析结果将有助于提高对N（星星）共振谱的理解，也有助于解决关于K介子核团簇存在与否的难题。其中ppK仅是，仅是最简单的表示。该项目应是一个为期两年半的职位博士的主题。