Fundamental Symmetry Tests with Trapped Antihydrogen: ALPHA at CERN/AD

阿尔法是欧洲核子研究中心的反物质实验。阿尔法团队有来自7个国家14个机构的科学家参与。其中超过三分之一的科学家来自加拿大的研究实验室和大学。加拿大团队(阿尔法-加拿大)在TRIUMF、UBC、SFU、U卡尔加里和约克大学都有成员。自2005年成立以来，它一直持有NSERC的重大项目资金，获得了2013年NSERC Polanyi奖，并为许多Alpha成就做出了重大贡献。*Alpha项目的目标是测量并比较‘反氢’(反H)-中性反物质的最简单原子形式-与普通氢的性质。在这样做的过程中，我们直接测试和挑战了关于物质和反物质之间的相似性和差异性(对称性)的基本理论，这个问题可以说是物理学中最大的悬而未决的问题之一。自2011年以来，阿尔法已经宣布了许多重大和高调的里程碑成就，包括：中性反物质的长期捕获(2011)，原理微波研究的证明(2012)，捕获反H的引力测量(2013)，原位陷阱诊断(2013-14)，以及反H电荷中立性的高精度测量[10^8(2014)中1部分，10^9(2016)中1部分]。*Alpha最近完成了一项重大升级，阿尔法-加拿大在NSERC的支持下对此做出了重大贡献。新的Alpha-2设备允许光学访问捕获的反H原子以进行精密激光光谱分析，这一实验目前正在欧洲核子研究中心进行。我们对Alpha-2的贡献包括：设计和制造新的反原子陷阱低温恒温器；升级探测器读数数据采集、陷阱电子学、激光和微波系统。到目前为止，阿尔法-2的工作包括反H收集率至少提高了10倍，利用腔存储激光对反H进行初步探测，以及脉冲莱曼-α激光系统的调试。阿尔法-加拿大团队在阿尔法-2调试和运行中发挥着重要作用，包括在探测器分析和脉冲激光系统操作方面提供领导。*阿尔法-加拿大和阿尔法与CFI和三个省合作，通过设计、建造和制造与阿尔法-2并行运行的第二台设备，进行了另一次基础设施升级。Alpha-g是一个系统，旨在测量中性反H的引力，并回答这样一个问题：如果一个反物质苹果掉落，它将如何坠落？*这项提案要求提供资金，以支持一个令人兴奋和高度引人注目的三年研究计划。它将导致有史以来第一次反H原子的激光光谱分析和冷却，改进对其超精细分裂的精确测量，以探测基本物理，首次测量其莱曼-α光谱，并首次观测到反H原子的重力自由落体。

ALPHA is an antimatter experiment based at CERN. The ALPHA Collaboration involves scientists from 14 institutions in 7 countries. Over one-third of these scientists come from Canadian research laboratories and universities. The Canadian team (ALPHA-Canada) has members at TRIUMF, UBC, SFU, UCalgary, and YorkU. It has held major project funding from NSERC since its inception in 2005, received the 2013 NSERC Polanyi Award, and has made significant contributions to numerous ALPHA achievements.***The goal of the ALPHA project is to measure and compare the properties of 'antihydrogen' (anti-H) - the simplest atomic form of neutral antimatter - with those of ordinary hydrogen. In doing so, we directly test and challenge fundamental theories about similarities and differences (‘symmetries') between matter and antimatter, an issue that is arguably one of the greatest unsolved problems in physics. Since 2011, ALPHA has announced many significant and high profile milestone achievements, including: long term trapping of neutral antimatter (2011), proof of principle microwave studies (2012), gravitational force measurements on trapped anti-H(2013), in situ trap diagnostics (2013-14) and high precision measurements of the charge neutrality of anti-H [1 part in 10^8 (2014), 1 part in 10^9 (2016)].***ALPHA recently completed a major upgrade, to which ALPHA-Canada made major contributions with NSERC support. The new ALPHA-2 apparatus allows optical access to trapped anti-H for precision laser spectroscopy, experiments that are currently underway at CERN. Our contributions to ALPHA-2 included: design and fabrication of the new anti-atom trap cryostat; upgrades to the detector readout data acquisition, trap electronics, laser, and microwave systems. Work to date with ALPHA-2 includes at least 10-fold improvement in anti-H collection rates, initial probing of anti-H with cavity-stored laser light, and commissioning of a pulsed Lyman-α laser system. The ALPHA-Canada team plays a prominent role in ALPHA-2 commissioning and operation, including providing leadership on detector analysis and pulsed laser system operation.***In partnership with CFI and three provinces, ALPHA-Canada and ALPHA have undertaken another infrastructure upgrade through design, construction, and fabrication of a second apparatus to run in parallel with ALPHA-2. ALPHA-g is a system designed to measure the gravitational forces on neutral anti-H and answer the question “If an antimatter apple was dropped, how would it fall?”***This proposal requests funding to support an exciting and highly-visible three-year program of research. It will result in the first-ever laser spectroscopy and cooling of atomic anti-H, improved measurements of the its hyperfine splitting at a precision that probes fundamental physics, first measurements of its Lyman-α spectra, and the first-ever observation of gravitational free-fall of anti-H.