相关实验视频
Updated: Jul 12, 2025
10:42
Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh
Published on: May 3, 2019
6.8K
概括
精确的时钟同步对于天引力波任务至关重要. 这项研究展示了一种基于激光的新型时钟传输系统,实现了高精度,满足了探测微弱信号的任务要求.
科学领域:
- 天体物理学 天体物理学
- 激光干扰计是指激光干扰计.
- 计量学 计量学 计量学
背景情况:
- 基于太空的重力波探测任务,如天,需要精确的航天器间时钟同步.
- 激光相位-侧带时钟转移对于测量航天器之间的相对时钟动至关重要.
研究的目的:
- 为天任务开发和验证航天器间时钟动读数的系统方案.
- 为了满足引力波信号提取的严格时间要求.
主要方法:
- 通过使用时间延迟干扰计算法来导出时钟传输链路要求.
- 构建了一个双向激光干扰仪系统,用于弱光时钟传输 (低于nW功率,~50μs延迟).
- 模拟的跨航天器多普勒频率转移使用激光频率调制.
主要成果:
- 确定GHz频率合成器作为50mHz以下的主要噪声源.
- 在40 fs/Hz1/2以下达到剩余的时钟动噪声,在6 mHz以上.
- 在1000秒时显示的分数频率不稳定性<6.7 × 10-17,符合天任务标准.
结论:
- 开发的激光时钟转移方案满足了天的同步需求.
- 在噪声校正后,载体相位测量精度达到1 × 10-4周期/Hz1/2 6mHz以上.
- 该系统为未来航天任务的精确计时提供了可行的解决方案.
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