论文标题
从其振动模式的频率中约束Ligo测试质量内温度分布
Constraining temperature distribution inside LIGO test masses from frequencies of their vibrational modes
论文作者
论文摘要
测试质量的热失真以及其振动模式频率的热漂移构成了高级LIGO和高级处女座干涉仪操作的主要挑战，从而降低了光学效率，从而限制了灵敏度并可能导致不稳定性，从而减少了占空比。在本文中，我们证明了测试质量振动模式频率数据可用于克服其中一些困难。首先，我们得出了模式频率变化的一般表达，这是测试质量内温度分布的函数。然后，我们展示如何使用对温度分布的模式频率来识别观察到的振动模式的波功能。然后，我们显示监视多个振动模式的频率如何使测试质量内的温度分布受到强烈约束。最后，我们使用模拟证明了改善测试质量的热模型的潜力，从而提供了重要参数的独立和改进的估计值，例如涂料吸收系数和点吸收器的位置。
Thermal distortion of test masses, as well as thermal drift of their vibrational mode frequencies, present a major challenge for operation of the Advanced LIGO and Advanced VIRGO interferometers, reducing optical efficiency, which limits sensitivity and potentially causing instabilities which reduce duty-cycle. In this paper, we demonstrate that test-mass vibrational mode frequency data can be used to overcome some of these difficulties. First, we derive a general expression for the change in a mode frequency as a function of temperature distribution inside the test mass. Then we show how the mode frequency dependence on temperature distribution can be used to identify the wavefunction of observed vibrational modes. We then show how monitoring the frequencies of multiple vibrational modes allows the temperature distribution inside the test mass to be strongly constrained. Finally, we demonstrate using simulations, the potential to improve the thermal model of the test mass, providing independent and improved estimates of important parameters such as the coating absorption coefficient and the location of point absorbers.
