Design and Characterization of Compact Discharge Units for Advanced LIGO

先进 LIGO 紧凑型放电装置的设计和表征

• 批准号: 0969488
• 负责人: Jens Gundlach
• 金额: $ 30万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-01 至 2013-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0969488&HistoricalAwards=false
• 关键词: Design; Characterization; Compact; Discharge; Units

One of the remaining risks for the success of the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) is excess noise due to charge accumulation on the mirrors used as test masses in the interferometer. Research funded by this award will lead to the construction of compact discharge units (CDUs) that can be used to mitigate the charge on the test masses. Each unit features a steerable, low-energy electron beam to neutralize positive charges and a wide angle UV beam to photo-eject negative charges. The CDUs will be optimized for size, reliability, and discharge current within the UV-radiation level tolerable for the optical coating of the Advanced LIGO test masses. Testing of the units will be performed with an existing torsion balance that can measure the absolute charge on an insulator with conducting surface.In fact, charge mitigation is important for a variety of precision mechanical experiments, including Advanced LIGO, torsion balances, and inertial masses in satellites. In all these systems, a sensitive test mass is electrically isolated from its surroundings. Charge accumulation can lead to spurious coupling between a test mass and nearby surfaces. This unwanted coupling leads to excess noise, degrading the performance of the experiments. The compact discharge unit can be used to reduce this extraneous noise by neutralizing charge on the test mass. Graduate students will participate in this project.

先进激光干涉仪引力波天文台（LIGO）成功的剩余风险之一是干涉仪中用作测试质量的反射镜上电荷积累造成的过量噪声。由该奖项资助的研究将导致紧凑型放电单元（cdu）的建设，该单元可用于减轻测试质量上的电荷。每个单元都有一个可操纵的低能电子束来中和正电荷，一个广角紫外线束来光射负电荷。cdu将在尺寸、可靠性和放电电流方面进行优化，放电电流在先进LIGO测试质量光学涂层可容忍的紫外线辐射水平范围内。单元的测试将使用现有的扭转天平进行，该天平可以测量具有导电表面的绝缘体上的绝对电荷。事实上，电荷减缓对各种精密机械实验都很重要，包括先进的LIGO、扭转平衡和卫星惯性质量。在所有这些系统中，敏感的测试质量都与周围环境电隔离。电荷积累会导致测试质量和附近表面之间的伪耦合。这种不必要的耦合会导致过量的噪声，降低实验的性能。紧凑的放电单元可以通过中和测试质量上的电荷来减少这种外来噪声。研究生将参与这个项目。