Star Formation out of the Magnetised Interstellar Medium

磁化星际介质中的恒星形成

• 批准号: 319967414
• 负责人: Professor Dr. Robi Stefan Banerjee
• 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: 2016
• 资助国家: 德国
• 起止时间: 2015-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/319967414?language=en
• 关键词: Star; Formation; out; Magnetised; Interstellar

Magnetic fields are an elemental part of the interstellar medium (ISM) which have a large impact on the dynamics of the ISM on various spatial scales. One long-standing issue is their influence on the formation of stars in galaxies. Similarly to thermal pressure, magnetic fields prevent contraction of otherwise self-gravitating gas clumps if they are strong enough. Therefore, gaseous overdensities must be magnetically supercritical, quantified by the mass-to-flux ratio, to collapse and to subsequently allow the formation of stars. There is increasing evidence that the ISM-field is rather strong (B > 6 muG) which gives rise to the question how supercritical cloud cores can be generated? To answer this question is the goal of this project. Within this proposed project we will test the two possible answers to this issue, namely the ambipolar diffusion (AD) mediated process, where locally the mass-to-flux is increased and the accumulation process, where gas is gathered over large distances. Therefore, we will study in detail the physics which impacts the AD-model (e.g. chemical and radiative ionisation processes) and we will self-consistently probe the accumulation process with global galactic simulations.

磁场是星际介质（ISM）的元素部分，它对ISM在各种空间尺度上的动力学有很大影响。一个长期存在的问题是它们对星系中恒星形成的影响。与热压类似，磁场如果足够强的磁场，则可以防止其本身自我磨碎的气体团块收缩。因此，气态过度必须是磁性超临界，通过质量到频率比量化，以塌陷并随后允许恒星的形成。越来越多的证据表明，ISM场相当强（B> 6杯），这引起了一个问题，该问题如何产生超临界的云芯？回答这个问题是该项目的目标。在这个拟议的项目中，我们将测试此问题的两个可能答案，即双极扩散（AD）介导的过程，在该过程中，局部质量到液压的增加和积累过程，在大距离内收集了气体。因此，我们将详细研究影响AD模型的物理学（例如化学和辐射电离过程），我们将通过全球银河系模拟来自言自语地探究积累过程。