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

ALPHA是欧洲核子研究中心的一项实验。ALPHA合作涉及来自8个国家15个机构的科学家。这些科学家中超过三分之一来自加拿大的研究实验室和大学。自2005年成立以来，加拿大团队一直获得NSERC的重大项目资助，并为许多ALPHA成就做出了重大贡献。ALPHA项目的目标是测量和比较“反氢”——中性反物质最简单的原子形式——与普通氢的某些性质。这样一来，这次合作将直接测试和挑战关于物质和反物质之间相似性和差异性（“对称性”）的基本理论，这一问题可以说是物理学中最大的未解决问题之一。近年来，ALPHA在追求其主要目标的过程中取得了许多重要而引人注目的里程碑，包括：低温冷却技术的新应用（2010年），中性反物质的稳定（2010年）和长期（2011年）捕获，以及捕获反氢的原理微波研究的证明（2012年）。ALPHA目前正在进行重大升级，加拿大小组在NSERC的支持下做出了重大贡献。新设备（ALPHA-2）将允许光学访问捕获的反氢，用于精确激光光谱，以及改进的微波光谱。ALPHA-Canada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，升级探测器读出系统和数据采集，新的（和改进的）陷阱电子设备，以及激光和微波系统。在这个提案中，我们要求资助一个令人兴奋和高度可见的三年研究计划。它将导致原子反氢的第一次激光冷却，对反氢超精细分裂的精度测量的改进，这是基础物理学的兴趣，以及反氢的1s-2s光谱的第一次演示。

ALPHA is an experiment based at CERN. The ALPHA collaboration involves scientists from 15 institutions in 8 countries. Over one-third of these scientists come from Canadian research laboratories and universities. The Canadian team has held major project funding from NSERC since its inception in 2005, and has made significant contributions to numerous ALPHA achievements. The goal of the ALPHA project is to measure and compare certain properties of 'antihydrogen' - the simplest atomic form of neutral antimatter - with those of ordinary hydrogen. In doing so, the collaboration will 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. In recent years, ALPHA has achieved many significant and high profile milestones in its pursuit of its primary goal, including: novel application of cryogenic cooling techniques (2010), stable (2010) and long term (2011) trapping of neutral antimatter, and proof of principle microwave studies of trapped antihydrogen (2012). ALPHA is currently undergoing a major upgrade, to which the Canadian group has made significant contributions with support from NSERC. The new apparatus (ALPHA-2) will allow optical access to trapped antihydrogen for precision laser spectroscopy, as well as improved microwave spectroscopy. ALPHA-Canada's contributions to ALPHA-2 include: design and fabrication of the new anti-atom trap cryostat, upgrades to the detector readout system and data acquisition, new (and improved) trap electronics, as well as laser and microwave systems. In this proposal, we request funding to support an exciting and highly-visible three year program of research. It will result in the first-ever laser cooling of atomic antihydrogen, an improved measurement of the antihydrogen hyperfine splitting at a precision that is of fundamental physics interest, and a first demonstration of 1s-2s spectroscopy in antihydrogen.