一种用于系外行星观测的光谱仪,校准在每秒厘米级别
Tobias Wilken1, Gaspare Lo Curto, Rafael A Probst
1Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching, Germany. tobias.wilken@mpq.mpg.de
Nature
|June 5, 2012
概括
激光频率可以精确校准天文光谱仪. 这一突破允许探测类似地球的系外行星,并以前所未有的准确度测量宇宙加速.
科学领域:
- 天文学和天体物理学
- 光学物理学 光学物理学
背景情况:
- 光谱仪的稳定性对于检测微妙的天文信号至关重要.
- 当前的校准方法限制了在辐射速度测量中可以达到的精度.
- 激光频率提供了一个高度稳定和准确的光源.
研究的目的:
- 用激光频率来校准一个天文光谱仪.
- 为了实现前所未有的短期多普勒转移可重复性.
- 为了证明探测类似地球的系外行星和宇宙加速的潜力.
主要方法:
- 使用激光频率作为天文光谱仪的校准光源.
- 实现了辐射速度测量的绝对校准.
- 监测了恒星HD 75289并重新计算了它的行星轨道.
主要成果:
- 证明了短时间多普勒转移的可重复性为2.5cm s(-1).
- 成功地重新校准了行星围绕恒星HD 75289.9的轨道.
- 取得的精度超过了以前在光谱仪校准方面的限制.
结论:
- 激光频率校准显著提高光谱仪的稳定性和精度.
- 这项技术为在可居住区探测地球质量系外行星铺平了道路.
- 通过精确的辐射速度监测,可以直接测量宇宙加速.
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