Gravitational wave detection by space laser interferometry
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摘要:为印证广义相对论和开拓引力波天文学窗口,引力波探测是当前国际研究热点. 本文围绕空间激光干涉引力波探测,对其科学意义、发展状况、关键技术等进行了回顾. 与地面激光干涉引力波探测相比,空间探测的工作频段更低,从10 -4»10 Hz,在工作距离为百万公里量级上,预计能探测到双致密星系统、超大质量比双黑洞绕转系统、中等质量比双黑洞绕转系统,以及星系合并引起的超大质量黑洞并合等波源. 为此,测距精度须达到皮米的量级,并且保证测距技术有效工作的无拖曳航天技术亦有很高的要求. 本文以欧洲的空间激光引力波探测计划为例,主要对上述两项技术进行分析和阐述,并展望了空间引力波探测在我国的发展趋势和前景.Abstract:Gravitational wave detection is now more than a mere veri¯cation of Einstein's relativity. It opens a brand-new window to explore gravitational wave astronomy, therefore attracts increasing attention of scientists from all over the world. Focusing on space laser interferometer gravitational wave detection, we give a comprehensive review on its scienti¯c objectives, recent status and key technologies. With arm-length being of million kilometers, a space detector works within a frequency band from 0.1mHz to 10Hz. Its possible sources include compact binary star system, extreme mass ratio inspiral, intermediate mass ratio inspiral, super mass black hole merge, etc. The success of space gravitational wave detection mission requires a pico-meter precision laser interferometer, and a state-of-the-art drag- free control system. Taking European space gravitational wave detector as an example, we analyze space laser interferometer and drag-free control system in detail. The trend and perspective of Chinese space gravitational wave detection mission are also discussed.
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