Galactic Gas Distribution and Cosmic-Ray Transport

银河气体分布和宇宙射线传输

• 批准号: 495252601
• 负责人: Privatdozent Dr. Torsten Enßlin
• 金额: --
• 依托单位: Max-Planck-Institut für Astrophysik (MPA)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/495252601?language=en
• 关键词: Galactic; Gas; Distribution; Cosmic; Ray

The interstellar medium of the Milky Way shows complex interactions of gas, dust, magnetic fields, starlight, and cosmic rays (CRs). Transport and interactions of CRs are closely related. They are further influenced by the spatial distribution of CR sources, galactic gas, starlight, and magnetic fields. Reconstructing the 3D structure of each of these quantities would be a major advance in Galactic astrophysics and would also help to better determine the others from measured data. We propose a series of Galactic 3D reconstructions with successively increasing complexity, of CR density, its source density, gas density, gas velocity, and other related quantities. For this purpose, we extend existing approaches to gas tomography (GIFT) and dust tomography based on numerical methods of information field theory (NIFTy). To reconstruct the source density, we will integrate the PICARD transport code into our NIFTy inference machinery. The science products of this project will be made publicly available and will enable a number of follow-up studies, such as 3D modelling of the Galactic magnetic field. In addition to the 3D maps, we will publish associated uncertainty maps and statistical summaries. Our goal is to greatly improve the simulation of transport and interaction of CRs also for the purpose of more accurately identifying their sources. The tomography methodology developed in this effort, which includes calculations of radiation transport, should also be useful for other fields, such as optical-acoustic medical imaging. To meet the challenges of this endeavour, we will combine our respective expert knowledge, which includes CR phenomenology, Bayesian inference, and numerical techniques.

银河系的星际介质显示了气体、尘埃、磁场、星光和宇宙射线（CRs）之间复杂的相互作用。cr的输运与相互作用密切相关。它们进一步受到CR源、星系气体、星光和磁场的空间分布的影响。重建这些数量的三维结构将是银河系天体物理学的重大进步，也将有助于更好地从测量数据中确定其他数量。我们提出了一系列的银河三维重建，其复杂性依次增加，CR密度，其源密度，气体密度，气体速度和其他相关量。为此，我们扩展了现有的基于信息场论数值方法的气体层析成像（GIFT）和尘埃层析成像（NIFTy）方法。为了重建源密度，我们将把PICARD传输代码集成到我们的NIFTy推理机器中。该项目的科学成果将向公众开放，并将使一些后续研究成为可能，例如银河磁场的三维建模。除了3D地图外，我们还将发布相关的不确定性地图和统计摘要。我们的目标是为了更准确地识别它们的来源，大大改进CRs的传输和相互作用的模拟。在这项工作中开发的断层扫描方法，包括辐射输运的计算，也应该对其他领域有用，如光学声学医学成像。为了迎接这一努力的挑战，我们将结合各自的专业知识，包括CR现象学，贝叶斯推理和数值技术。