Collaborative Research: The Physics of Accretion Disks

合作研究：吸积盘的物理学

• 批准号: 0908336
• 负责人: Julian Krolik
• 金额: $ 55.56万
• 依托单位: Johns Hopkins University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-01 至 2014-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0908336&HistoricalAwards=false
• 关键词: Collaborative; Research; Physics; Accretion; Disks

AST-0908336/0908869Krolik/HawleyArmed by an understanding that the fundamental mechanism of accretion is angular momentum transport due to magnetohydrodynamic (MHD) turbulence driven by the magneto-rotational instability, it has become possible to investigate at a detailed level the astrophysical properties of accretion onto black holes. With previous NSF support, this team has developed a suite of Newtonian and general relativistic MHD numerical simulation codes suitable for exploring the global properties of accretion flows onto black holes and the jets they sometimes generate. This collaborative project, led by Dr. Krolik, will now extend prior work to consider accretion thermodynamics and energetics, the impact of large-scale magnetic fields, and how an accretion flow oriented obliquely to the black hole rotation axis at large distances interacts with Lense-Thirring torques. Emphasis will be placed throughout on creating quantitative links between dynamical simulation data and observable properties.This work should provide genuine guidance for the controversy over how much large-scale magnetic flux may be brought deep into the accretion flow. It should also reveal how accretion flows stressed by magnetic fields with intrinsic large-scale structure may differ from those without. In addition, computing MHD stresses within the accretion flow is essential to the question of the extent of disk bending by gravitomagnetic forces, and it should soon be possible to calculate disk structure with sufficient resolution to address this issue.Both simulation codes and data from specific models will be made available to the community, strengthening the software infrastructure of the discipline. The project will provide graduate student training in numerical simulation techniques. Successful public outreach efforts based on simulation results will continue, including planetarium shows and television documentaries.

AST-0908336/0908869Krolik/Hawley认识到吸积的基本机制是由磁旋转不稳定性驱动的磁流体动力（MHD）湍流引起的角动量传输，因此可以详细研究吸积的天体物理性质到黑洞上。 在之前 NSF 的支持下，该团队开发了一套牛顿和广义相对论 MHD 数值模拟代码，适用于探索黑洞吸积流及其有时产生的喷流的全局特性。 这个由 Krolik 博士领导的合作项目现在将扩展之前的工作，以考虑吸积热力学和能量学、大尺度磁场的影响，以及长距离倾斜于黑洞旋转轴的吸积流如何与 Lense 相互作用-令人刺耳的扭矩。 重点将始终放在建立动态模拟数据和可观测特性之间的定量联系上。这项工作应该为关于有多少大规模磁通量可以深入吸积流的争论提供真正的指导。 它还应该揭示具有内在大尺度结构的磁场所施加的吸积流与没有大尺度结构的磁场所施加的吸积流有何不同。 此外，计算吸积流内的 MHD 应力对于磁引力力导致的盘弯曲程度问题至关重要，并且很快就可以以足够的分辨率计算盘结构来解决这个问题。模拟代码和数据都来自特定的模型将向社区提供，从而加强该学科的软件基础设施。 该项目将为研究生提供数值模拟技术的培训。 基于模拟结果的成功公共宣传工作将继续下去，包括天文馆节目和电视纪录片。