CDS&E: The development of open-source software with an application to modeling the formation of globular star clusters

CDS

• 批准号: 1615955
• 负责人: Greg Bryan
• 金额: $ 40.67万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-10-01 至 2020-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1615955&HistoricalAwards=false
• 关键词: CDS& development; open; source; software

Globular star clusters are among the oldest objects in our Universe, and understanding their origin has remained a great challenge to astrophysicists for many decades. This project will develop computer software employing a new numerical method to perform the calculations modeling the formation of these clusters of stars. This new computer software will enable better computer modeling of the astrophysics governing a variety of physical applications. It will also be the first such software to be made publicly available. The investigators will then use this software to create computer simulations that model the formation of globular star clusters, and they specifically seek to understand the apparent creation of multiple generations of stars in these globular clusters. This project's goals will advance the national interests of developing US leadership in physics and enhancing the US cyber infrastructure. In addition, the investigators will address the national underrepresentation of minorities in the sciences by funding a graduate student to participate in Columbia University's Bridge to the PhD in the Natural Sciences program. The investigators will train the student in the research program and will mentor the student through the early stages of his or her science career.More technically, the first part of this project lays out a systematic plan to develop a new open source moving-mesh code. Recent development of the moving-mesh method as a viable alternative to smoothed particle hydrodynamics and adaptive mesh refinement is a promising development. Moving-mesh hydrodynamics brings many desirable features including low-diffusion in bulk flows, Galilean invariance, and good shock handling. The software development uses modern design and coding techniques to produce an efficient, parallel code that will be capable of using a wide range of physics and that is easy to use and modify. It will use the widely used Python language combined with Cython (a static Python compiler) in computationally intensive parts. Coding will be modular and designed to allow easy and flexible extension to all parts of the code. The second part of this project is to simulate the formation of globular clusters. The code will be applied to a three-part plan for understanding globular cluster formation: (1) modeling the fragmentation and collapse of idealized low-metallicity gas clouds to understand the relative importance of global collapse and fragmentation; (2) using cosmological simulations to identify the physical properties of gas undergoing rapid colliding flows, a prerequisite to bring together a large amount of gas in a small region for GC formation; and (3) exploring the ability of gas outflows from the proposed sources of enriched material to be re-incorporated into a second generation of stars.

球状星团是我们宇宙中最古老的物体之一，几十年来，了解它们的起源一直是天体物理学家面临的一个巨大挑战。该项目将开发计算机软件，采用一种新的数值方法来模拟这些星团的形成。这种新的计算机软件将能够更好地对天体物理学进行计算机建模，从而控制各种物理应用。它也将是第一个向公众开放的此类软件。然后，研究人员将使用该软件创建计算机模拟，模拟球状星团的形成，他们特别寻求理解这些球状星团中多代恒星的明显形成。该项目的目标将促进发展美国在物理学领域的领导地位和加强美国网络基础设施的国家利益。此外，研究人员将通过资助一名研究生参加哥伦比亚大学自然科学博士项目的桥梁项目，解决全国少数民族在科学领域代表性不足的问题。研究人员将在研究项目中对学生进行培训，并在学生科学生涯的早期阶段对其进行指导。更技术性的是，这个项目的第一部分列出了一个系统的计划来开发一个新的开源移动网格代码。最近发展起来的移动网格方法作为光滑粒子流体力学和自适应网格细化的可行替代方法是一个有前途的发展。动网格流体力学具有许多理想的特性，包括低扩散，伽利略不变性和良好的冲击处理。软件开发使用现代设计和编码技术来生成高效的并行代码，这些代码将能够使用广泛的物理特性，并且易于使用和修改。它将在计算密集型部分使用广泛使用的Python语言与Cython（静态Python编译器）相结合。编码将是模块化的，设计允许轻松灵活地扩展到代码的所有部分。这个项目的第二部分是模拟球状星团的形成。该代码将应用于一个由三部分组成的计划，以了解球状星团的形成：(1)对理想的低金属丰度气体云的破碎和坍缩进行建模，以了解全球坍塌和破碎的相对重要性；(2)利用宇宙学模拟，确定了经历快速碰撞流的气体的物理性质，这是将大量气体聚集在一个小区域形成GC的先决条件；(3)探索从提出的富集物质来源流出的气体重新并入第二代恒星的能力。