毫米和亚毫米地面望远镜的候选地点:欧亚亚洲亚毫米望远镜项目大气评级
Artem Y Shikhovtsev1, Pavel G Kovadlo1, Philippe Baron2
1Institute of Solar-Terrestrial Physics, The Siberian Branch of the Russian Academy of Sciences, Irkutsk 664033, Russia.
Sensors (Basel, Switzerland)
|April 12, 2025
概括
这项研究使用ERA-5数据评估了毫米/亚毫米望远镜位置的水蒸气. 结果显示,对于天文观测而言,大气条件充满希望,支持欧亚亚亚毫米级望远镜项目.
科学领域:
- 天文学和天体物理学
- 大气科学 大气科学
- 地质物理学 地质物理学
背景情况:
- 地球的大气层,特别是水蒸气,对地面天文观测有很大影响,特别是对于毫米/亚毫米望远镜.
- 精确评估由于水蒸气导致的大气不透明度对于选址和确定望远镜能力至关重要.
- 现有的文献对研究的大欧亚地区的水蒸气含量覆盖范围有限.
研究的目的:
- 分析水蒸气含量和空间分布在一个大,未经研究的区域,用于天文现场测试.
- 通过ERA-5再分析数据来完善沉式水蒸气 (PWV) 估计,并与GNSS衍生的PWV进行验证.
- 评估用于毫米/亚毫米望远镜的潜在地点,包括Khulugaisha峰,Tashanta和特殊天体物理学天文台.
主要方法:
- 利用ERA-5再分析数据来得出沉式水蒸气 (PWV) 的空间分布.
- 对水蒸气 (Heff) 的特征垂直尺度和相对高度差异进行了校正的PWV数据.
- 与全球导航卫星系统 (GNSS) 数据对比验证的ERA-5衍生PWV,实现了高相关性 (皮尔森系数>0.9).
主要成果:
- 在一个大区域 (20°N-70°N,35°E-120°E) 中生成纠正的PWV的空间分布.
- 计算了Khulugaisha峰和Tashanta等潜在地点的中位大气不透明度.
- 在重新分析衍生的PWV和GNSS衍生的PWV之间证明了很高的相关性,证实了数据可靠性.
结论:
- 这项研究表明,在评估地点进行毫米波天文观测时,大气条件充满希望.
- 精确的PWV估计为地面毫米/亚毫米望远镜的现场测试提供了有价值的工具.
- 通过确定合适的地点,这些发现支持欧亚亚亚毫米次望远镜 (ESMT) 项目的发展.
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