论文标题
三维气体图的贝叶斯推断：ii。银河系HI
Bayesian inference of three-dimensional gas maps: II. Galactic HI
论文作者
论文摘要
来自原子氢（HI）的21厘米发射是星际介质的结构和动力学最重要的示踪剂之一。多亏了银河旋转，该线被多普勒移动，并且假设速度场的模型，可以沿着视线对气线调查的数据进行分析。但是，鉴于我们在银河系中的有利位置，这种重建遭受了许多歧义。在这里，我们认为可以通过利用塑造其物理过程所暗示的气体密度的空间相干性来治愈这些方法。我们采用了一个贝叶斯推理框架，该框架允许重建HI的三维图并量化其不确定性。我们使用HI4PI汇编的数据来生成三维的银河系地图。重建的密度显示了各种尺度上的结构。特别是，可以轻松地识别出某些马刺和螺旋臂。我们讨论表面质量密度以及径向和垂直谱的形态。重建的三维HI密度可在https://doi.org/10.5281/zenodo.5956696获得。
The 21-cm emission from atomic hydrogen (HI) is one of the most important tracers of the structure and dynamics of the interstellar medium. Thanks to Galactic rotation, the line is Doppler shifted and, assuming a model for the velocity field, data from gas line surveys can be deprojected along the line of sight. However, given our vantage point in the Galaxy, such a reconstruction suffers from a number of ambiguities. Here, we argue that those can be cured by exploiting the spatial coherence of the gas density that is implied by the physical processes shaping it. We have adopted a Bayesian inference framework that allows reconstructing the three-dimensional map of HI and quantifying its uncertainty. We employ data from the HI4PI compilation to produce three-dimensional maps of Galactic HI. The reconstructed density shows structure on a variety of scales. In particular, some spurs and spiral arms can be identified with ease. We discuss the morphology of the surface mass density and the radial and vertical profiles. The reconstructed three-dimensional HI densities are available at https://doi.org/10.5281/zenodo.5956696.
