The Fate of Cold Clouds in Galaxy Outflows

星系外流中冷云的命运

• 批准号: 343993325
• 负责人: Professor Dr. Marcus Brüggen, Ph.D.
• 金额: --
• 依托单位: Hamburger Sternwarte
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2017
• 资助国家: 德国
• 起止时间: 2016-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/343993325?language=en
• 关键词: Fate; Cold; Clouds; Galaxy; Outflows

In this proposal, we study the fate of cold gas in supersonic galactic winds. Galaxy outflows play a key role in the history of galaxy formation, driving multiphase material from deep within the densest regions of galaxies out into the rarified fringes of the circumgalactic medium. Even the presence of this cold and fast gas is surprising, as simple theoretical estimates predict that it should be disrupted by interactions with the hot wind well before it is accelerated to significant velocities. The key issue in this case is the ability for the hot wind to accelerate cold material, before it disrupts it.We identify three objectives of this proposal that are essential to answer the one central question of this proposal: Can anisotropic conduction in magnetised outflows prevent the disruption of cold clouds? 1. Develop a module for implicit anisotropic conduction in the AMR MHD code FLASH. 2. Perform parameter study of cold clouds in magnetised outflow and measure the lifetime of clouds. 3. Find analytic expressions for lifetimes and put the results of the simulations into the context of the cycle of matter in galaxies.

在这个提议中，我们研究了超音速星系风中冷气体的命运。星系外流在星系形成的历史中扮演着关键的角色，它将多相物质从星系致密区域的深处驱动到环星系介质的稀薄边缘。即使这种冷而快的气体的存在也是令人惊讶的，因为简单的理论估计预测，它应该在加速到显著速度之前就被与热风的相互作用所破坏。在这种情况下，关键问题是热风加速冷材料的能力，在它破坏它之前，我们确定了这个建议的三个目标，是必不可少的回答这个建议的一个核心问题：可以在磁化流出的各向异性传导防止冷云的破坏？1.在AMR MHD程序FLASH中开发隐式各向异性传导模块。2.对磁化外流中的冷云进行参数研究，并测量云的寿命。3.找到寿命的解析表达式，并将模拟结果放入星系中物质循环的背景中。