Electron Detectors for High Precision Compton Polarimetry in Parity Violating Electron Scattering using HVMAPS

使用 HVMAPS 进行宇称破坏电子散射高精度康普顿旋光测量的电子探测器

• 批准号: SAPEQ-2017-00007
• 负责人: Gericke, Michael
• 金额: $ 2.85万
• 依托单位: University of Manitoba
• 依托单位国家: 加拿大
• 项目类别: Subatomic Physics Envelope - Research Tools and Instruments
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=616793
• 关键词: Electron; Detectors; Precision; Compton; Polarimetry

At Jefferson Laboratory, North America's premiere electron scattering laboratory, parity-violating electron scattering (PVES) experiments are measuring quantities with extreme precision in order to determine nuclear and nucleon properties and even to test our most basic understanding of matter - the Standard Model of Particles and Interactions. In order to make highly precise measurements you need to do two things - make many measurements of the same thing and make sure that the error on each measurement is small. The first is related to the statistical uncertainty of an experiment, the second to the systematic uncertainty. Advances in computing technology have made it possible for nuclear and particle physics experimenters to record and digitize their data, and to take many millions of samples. This allows us to measure quantities with such precision that we can make measurements of quantities on the order of parts per billion and smaller. One of the most important sources of systematic uncertainty for PVES measurements is the magnitude of the polarization of the electron beam. The polarization has to be measured very precisely and cross-checked with different methods. One method is to use a Compton polarimeter to measure the known asymmetry in Compton scattering of the polarized electron beam with polarized laser light. The benefit of doing this is that it is non-invasive - so few electrons interact with the laser light that the measurement can be made continuously without interfering with the electron beam that goes on to be used in the main experiment. There are also multiple ways that the polarization can be measured in this case - by measuring the Compton scattered electrons or photons. In order to keep up with the requirements of the experiments, the Compton polarimeter in Hall A of Jefferson Lab requires a major upgrade. It is getting upgrades to its laser, beamline, data acquisition, and its photon and electron detectors. Canadian physicists at the Universities of Manitoba and Winnipeg will be responsible for the electron detector, so that the Compton polarimeter will be able to meet the needs of the future PVES program at Jefferson Lab - forging the way into the Precision Frontier.

在杰斐逊实验室，北美首屈一指的电子散射实验室，宇称违反电子散射（PVES）实验正在以极高的精度测量数量，以确定核和核子的性质，甚至测试我们对物质的最基本理解-粒子和相互作用的标准模型。为了进行高精度的测量，你需要做两件事-对同一件事进行多次测量，并确保每次测量的误差很小。第一个与实验的统计不确定性有关，第二个与系统不确定性有关。计算技术的进步使核物理和粒子物理实验者能够记录和分析他们的数据，并采集数百万个样本。这使我们能够以这样的精度测量数量，我们可以测量十亿分之一或更小的数量级。PVES测量的系统不确定性的最重要来源之一是电子束的偏振的大小。必须非常精确地测量偏振，并使用不同的方法进行交叉检查。一种方法是使用康普顿偏振计来测量偏振电子束与偏振激光的康普顿散射中的已知不对称性。这样做的好处是它是非侵入性的-很少有电子与激光相互作用，因此可以连续进行测量，而不会干扰主要实验中使用的电子束。在这种情况下，也有多种方法可以测量偏振-通过测量康普顿散射的电子或光子。为了跟上实验的要求，杰斐逊实验室A厅的康普顿旋光仪需要进行重大升级。它正在升级其激光器，光束线，数据采集，以及光子和电子探测器。马尼托巴大学和温尼伯大学的加拿大物理学家将负责电子探测器，这样康普顿偏振计将能够满足杰斐逊实验室未来PVES计划的需求--为精密前沿开辟道路。