Thermal Noise Research for Advanced LIGO Interferometers

寻找引力波需要探测器不被可能掩盖引力波信号的噪声源所淹没。 热噪声是最严重的罪犯之一。 锡拉丘兹大学的Saulson和他的团队提出的研究计划旨在了解影响引力波探测器的热噪声源，并设计减少这些源的影响的方法。减少干涉仪光学系统和测试质量及其悬挂系统产生的热噪声的关键是设计最小化机械能耗散的系统。 锡拉丘兹小组将开发一种测量LIGO光学悬挂线横向振动的方法，并将对包括熔融石英和蓝宝石在内的几种材料的机械耗散率进行高灵敏度测量，以确定它们用作干涉仪光学和测试质量的相对优点。 他们还将测量已为LIGO光学提出的各种镜面涂层材料中的能量耗散，并将探索冷却这些镜面以进一步降低热噪声的可能性。

The search for gravitational waves requires detectors that are not overwhelmed by noise sources that can mask gravitational wave signals. Thermal noise is one of the worst offenders. The research program proposed by Saulson and his group at Syracuse University is directed toward understanding the sources of thermal noise that effect gravitational wave detectors and to devise methods to reduce the effects of these sources.The key to reducing thermal noise generated by interferometer optics and test mass, and their suspension systems, is to design systems that minimize mechanical energy dissipation. The Syracuse group will develop a means for measuring the transverse vibrations of LIGO optics suspension wires, and will make high sensitivity measurements of mechanical dissipation rates of several materials, including fused silica and sapphire, to determine their relative merits for use as interferometer optics and test masses. They will also measure energy dissipation in a variety of mirror coating materials that have been proposed for LIGO optics and will explore the possibility of cooling these mirrors to further reduce thermal noise.