Spin Observables in Hadron Spectroscopy

强子谱中的自旋可观测值

• 批准号: 1306418
• 负责人: Tanja Horn
• 金额: $ 30.11万
• 依托单位: Catholic University of America
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-08-01 至 2017-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1306418&HistoricalAwards=false
• 关键词: Spin; Observables; Hadron; Spectroscopy

The scattering of high-energetic photons has been studied for many decades. The long interest in this endeavor is largely motivated by the study of nucleon and meson excitations, which manifest themselves as specific configurations of quarks or as gluonic excitation. The excitation of the glue that holds quarks and antiquarks closely together in mesons is predicted by the theory of strong interaction but has not been experimentally established. The GlueX experiment being constructed at the Thomas Jefferson National Accelerator Facility (JLab) in Newport News, VA, will be devoted to the search for such excitation. By using a high-energetic, highly polarized photon beam and a high-resolution detector with complete angular coverage, the GlueX experiment is predetermined to settle the question. Through NSF support, CUA is able to proceed with constructing and maintaining the broad-band tagging hodoscope and the polarized photon source for this experiment. Moreover, for many years CUA has been a leading institution in the polarized target program at JLab, aimed to measure all components of the scattering amplitudes in form of polarization observables, and thus to disentangle unambiguously the resonant contributions to the scattering. The grant provided by NSF will also support CUA's continuing efforts in the analysis of data taken on frozen-spin targets in JLab's Hall B.Their research aims for settling long-standing questions in our understanding of nuclear matter, which is comprised of quarks and gluons. To this end they develop state-of-the-art equipment and advanced software packages. Students and postdoctoral researchers are strongly involved in this effort. Their training under professional guidance will strengthen their analytical competence and prepare them for responsible and leading positions in the modern technological society.

数十年来研究了高能光子的散射。对这项努力的长期兴趣在很大程度上是由核子和介子激发的研究激发的，这些激发表现为夸克的特定构型或gluonic兴奋。强烈相互作用的理论预测了在介子中紧密地将夸克和古怪凝聚在一起的胶水的激发，但尚未实验确定。在弗吉尼亚州纽波特新闻（Newport News）的托马斯·杰斐逊国家（Thomas Jefferson）国家加速器设施（JLAB）建造的Gluex实验将致力于寻找这种激发。通过使用具有完全角度覆盖的高能，高极化的光子束和高分辨率检测器，预先确定了Gluex实验以解决该问题。通过NSF支持，CUA能够继续构建和维持该实验的宽带标记和偏振光子源。此外，多年来，CUA一直是JLAB两极分化目标计划中的领先机构，旨在测量以极化可观察到的形式测量散射幅度的所有组成部分，从而明确地解散了对散射的共振贡献。 NSF提供的赠款还将支持CUA在JLAB大厅中对冷冻自旋目标进行的数据进行分析。目的是在我们对核物质的理解中解决长期存在的问题，这是由夸克和gluons组成的。为此，他们开发了最先进的设备和高级软件包。学生和博士后研究人员强烈参与了这项工作。他们在专业指导下的培训将增强其分析能力，并为他们在现代技术社会中的负责任和领导地位做好准备。