Thermally excited vibrations of the mirrors of laser interferometer gravitational-wave detectors.
Thermally excited vibrations of the mirrors of laser interferometer gravitational-wave detectors.
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DOI：
10.1103/physrevd.52.577
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发表时间：
1995-07
期刊：
影响因子：
--
通讯作者：
Gillespie;Raab
中科院分区：
文献类型：
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作者：
Gillespie;Raab
使用激光干涉仪引力波探测器计算热激发镜面振动对长度测量的影响，并估计预测镜面相对于其质心的布朗运动必须包括的振动模式的数量。这些计算既考虑了反射镜振动模式的完整三维形状，又考虑了干涉仪光学模式的空间形状。找到必须包含在完整热噪声估计中的模式数量的收敛模式；必须考虑声波波长大于激光束光斑尺寸的所有振动模式。当考虑到反射镜和光学模式的完整几何形状时，与 LIGO（激光干涉仪引力波天文台）干涉仪相关的反射镜和激光参数的引力波频率带宽中的热噪声功率大约比早期估计中获得的噪声大 6 倍，早期估计通常只考虑最低的几种模式。如果镜面振动热噪声是检测某些天体物理源的限制噪声源，那么噪声功率的差异将导致这些源的估计确定率相差 15 倍。
The effect of thermally excited mirror vibrations on length measurements using a laser interferometer gravitational-wave detector is calculated, and the number of vibrational modes which must be included to predict the Brownian motion of the mirror surface relative to its center of mass is estimated. These calculations account for both the full three-dimensional shape of the vibrational modes of the mirrors and the spatial shape of the optical modes of the interferometer. A convergence pattern for the number of modes which must be included in a complete thermal noise estimate is found; all vibrational modes with acoustic wavelengths greater than the laser beam spot size must be considered. When the full geometries of the mirror and the optical mode are taken into account, the thermal noise power in the gravitational-wave frequency bandwidth for mirror and laser parameters relevant to the LIGO (Laser Interferometer Gravitational-Wave Observatory) interferometer is approximately a factor of 6 larger than the noise obtained in earlier estimates which typically considered only the lowest few modes. If mirror vibrational thermal noise were the limiting noise source for the detection of some astrophysical sources, then this difference in noise power would result in a factor of 15 difference in estimated determination rates for these sources.