RUI -- Further Optical Charge Studies with the Trinity University Kelvin Probe

激光干涉仪引力波天文台(LIGO)对信号频率接近100赫兹的引力波最为敏感。在这些频率下，一个潜在的噪声源是光学表面电荷的运动，它可能是通过与灰尘的研磨接触、与其他材料的接触产生的，或者可能是由静电驱动的极化产生的。电荷干扰光学元件的位置控制，吸引灰尘到光学表面，并产生起伏的电场，从而产生噪声。噪声的贡献取决于电荷的大小和电荷运动的关联时间。这些量的合理值表明，充电可能是Advanced LIGO的一个限制噪声源。该奖项支持一项旨在探索介质充电的基本物理原理以及减轻其对Advanced LIGO影响的方法的研究计划。由PI通过之前的NSF支持开发的三一大学实验室将用于一系列实验，包括高级LIGO组件可能产生静电充电的各种方式，减轻充电的测试方法，以及研究充电如何在引力波探测器中实际产生噪声。鉴于2006年在LIGO利文斯顿天文台看到的电荷噪声，以及最近发现的暴露在与Advanced LIGO中的电极类似的电极上充电的现象，这项研究可能对Advanced LIGO至关重要。这项研究对其他现有的、未来的和设想的地面重力波干涉仪也很重要，以便在其最敏感的频率范围内降低噪声。此外，三一大学的持续充电研究为尖端领域的本科生提供了真实的研究体验；十多名三一学生参与了LIGO相关项目和论文，出版了作者，在州和全国会议上展示了他们的结果，因他们的成就而获奖，并进入了与物理相关的成功职业生涯。

The Laser Interferometer Gravitational-Wave Observatory (LIGO) is most sensitive to gravitational waves at signal frequencies near 100 Hz. One potential noise source at these frequencies is the motion of surface charge on optics, which can be generated through abrasive contact with dust, contact with other materials, or possibly from polarization by an electrostatic drive. Charge contributes noise by interfering with the position control of optics, attracting dust to the optical surface, and generating fluctuating electric fields. The noise contribution depends on the charge magnitude and the correlation time for charge motion. Reasonable values for these quantities suggest that charging might be a limiting noise source for Advanced LIGO. This award supports a research program with the goal of exploring the underlying physics of dielectric charging and methods to mitigate its impact on Advanced LIGO. The laboratory at Trinity University developed by the PI through prior NSF support will be used for a number of experiments including various ways Advanced LIGO components might produce electrostatic charging, testing methods to mitigate the charging, and studying how charging actually produces noise in gravitational wave detectors. This research could be of crucial importance to Advanced LIGO, due to the charge noise witnessed at LIGO Livingston Observatory in 2006 and the recent discovery of charging from exposure to an electrode similar to one of those in Advanced LIGO. The research is also important for other existing, future, and envisioned ground-based gravitational wave interferometers in order to reduce noise in their most sensitive frequency range. In addition, continued charging research at Trinity University provides a real-word research experience to undergraduates in a cutting-edge field; over a dozen Trinity students have participated in LIGO-related projects and theses, have been published authors, have presented their results at state and national meetings, have won awards for their accomplishments, and have moved on to successful physics-related careers.