Constraining Double Degenerate Mergers

限制双重简并合并

• 批准号: 0806720
• 负责人: Francis Timmes
• 金额: $ 50.13万
• 依托单位: Arizona State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-01 至 2012-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0806720&HistoricalAwards=false
• 关键词: Constraining; Double; Degenerate; Mergers

By virtue of their use as standard candles, Type Ia supernovae are key tools in our quest to measure cosmological parameters, to probe the nature of dark energy, to understand the origin of matter, and to unravel the final fate of the universe. However, despite their adoption as distance indicators, questions of possible systematic effects remain open. Observations of individual Type Ia supernova explosions, double white dwarf binary systems, and Type Ia supernova rates in galaxies suggest that they may originate from different progenitor systems and may depend on the population of the host galaxy.Here, a comprehensive theoretical analysis will be undertaken that will examine merging white dwarfs as a pathway for producing Type Ia supernova. The hope is to better understand possible systematic effects and thereby improve the fidelity of future cosmological observations. The work is expected to lead to an understanding of the Type Ia supernova features produced from double-degenerate mergers based on first-principles physics that can be tested against current and future observations conducted by instruments such as the Supernovae Ia Progenitor Survey (SPY), Large Synoptic Survey Telescope (LSST) and Joint Dark Energy Mission (JDEM). The analysis includes developing a variety of double white dwarf Type Ia supernova progenitor systems, multi-dimensional simulations of the dynamical merger event with better mass resolution and input physics than previous studies, and statistical tools to generate a set of models that are in the best agreement with the observations of double white dwarf binary systems and double-degenerate Type Ia supernova candidates. This research will also impact a variety of other areas including cosmology, numerical methods, stellar evolution, massively parallel simulations, and galaxy evolution. This research will also promote national and international partnerships, specifically the LSST consortium and the JDEM enterprise. The project will serve as trans-disciplinary platform for training young scientific talent through the support of a postdoctoral research fellow and the results will be integrated into large classes for undergraduate non-science majors that are intrinsically diverse. Through writing, teaching and public lectures, the team will also broadly disseminate their results to the public. The codes developed here, including software for stellar evolution, nuclear reaction networks, equations of state, thermal conductivities, deflagrations, detonation, numerical methods and hydrodynamics will continue to be added to and release to the public throughout the research.

由于它们被用作标准蜡烛，Ia型超新星是我们寻求测量宇宙学参数、探测暗能量性质、理解物质起源和解开宇宙最终命运的关键工具。然而，尽管它们被采用为距离指标，但可能的系统性影响问题仍然悬而未决。对单个Ia型超新星爆发、双白色矮星双星系统和星系中Ia型超新星速率的观测表明，它们可能起源于不同的祖先系统，并且可能取决于宿主星系的人口。在这里，将进行全面的理论分析，以检验合并白色矮星作为产生Ia型超新星的途径。希望是更好地理解可能的系统效应，从而提高未来宇宙学观测的保真度。这项工作预计将导致基于第一原理物理学的双简并合并产生的Ia型超新星特征的理解，可以通过超新星Ia始祖巡天（SPY），大型综合巡天望远镜（LSST）和联合暗能量使命（JDEM）等仪器进行的当前和未来观测进行测试。分析包括开发各种双白色矮Ia型超新星的祖先系统，多维模拟的动力学合并事件更好的质量分辨率和输入物理比以前的研究，和统计工具，以产生一组模型，是在最好的协议与双白色矮双星系统和双退化Ia型超新星候选人的观察。这项研究还将影响其他各种领域，包括宇宙学，数值方法，恒星演化，大规模并行模拟和星系演化。这项研究还将促进国家和国际伙伴关系，特别是LSST财团和JDEM企业。该项目将通过博士后研究员的支持，作为培养年轻科学人才的跨学科平台，其成果将被纳入本质上多样化的本科非科学专业的大班。通过写作、教学和公开讲座，该小组还将向公众广泛传播他们的成果。在这里开发的代码，包括恒星演化，核反应网络，状态方程，热导率，爆燃，爆炸，数值方法和流体力学的软件，将在整个研究过程中继续添加并向公众发布。