刘章韬,林浦,张靖毅,杨浩楠,高扬

• 1:中山大学物理与天文学院天文系

摘要(Abstract)：

氢元素是宇宙中占比最高的重子物质，其中大部分以氢原子的形式存在。中性氢原子波长为21cm的超精细结构谱线，即中性氢21cm线，是较强的射电天文源，可以反映宇宙重子物质的分布。这里我们介绍在中山大学3.2米射电望远镜实验平台上开展的银河系中性氢21cm线观测实验，通过实际天文观测展示了从时域信号中获取动态频谱，以及通过时间和频率并道提高谱线信噪比的过程。同时，本文还介绍了射电望远镜的观测模式，并根据观测需要实现了望远镜自动巡天。在选做实验中，我们完成了银盘中性氢分布成图，并通过分析计算出太阳与银河系中心的距离，同时根据谱线红移计算出银河系旋转曲线。本文为“面向天文、物理和多个工科专业的射电望远镜实验平台”专题下篇，上篇是太阳流强时域变化实验，本专题为射电天文观测教学提供参考。

关键词(KeyWords)： 射电天文学;天文观测教学;自动化控制;中性氢;银河系巡天

Abstract:

Keywords:

基金项目(Foundation):

作者(Author): 刘章韬,林浦,张靖毅,杨浩楠,高扬

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