Thermal Noise Research for Advanced LIGO Interferometers

寻找引力波需要的探测器不会被噪声源淹没，因为噪声源会掩盖引力波信号。热噪声是最严重的罪魁祸首之一。索尔森和他在锡拉丘兹大学的研究小组提出的研究计划旨在了解影响引力波探测器的热噪声的来源，并设计出减少这些来源影响的方法。降低干涉仪光学和测试质量及其悬挂系统产生的热噪声的关键是设计使机械能量耗散最小化的系统。Syracuse小组将开发一种测量LIGO光学悬吊线横向振动的方法，并将对几种材料（包括熔融二氧化硅和蓝宝石）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。他们还将测量为LIGO光学提出的各种反射镜涂层材料的能量耗散，并将探索冷却这些反射镜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.