Massive Stellar Evolution, Supernovae, and Nucleosynthesis

大规模恒星演化、超新星和核合成

• 批准号: 0909129
• 负责人: Stanford Woosley
• 金额: $ 43.36万
• 依托单位: University of California-Santa Cruz
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2013-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0909129&HistoricalAwards=false
• 关键词: Massive; Stellar; Evolution; Supernovae; Nucleosynthesis

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). Dr. Woosley will continue his extensive research on the origin of the elements and the end points of stellar evolution. This includes the evolution of massive stars (heavier than about 8 solar masses) through all stages of their lives, modeling their explosions and appearance as supernovae, calculating the detailed production of the isotopes of all the elements, and examining the properties of the neutron stars and black holes they leave behind. A major survey involving a large number of model stars will be completed and the results made available to the community. A limited range models will also be explored for rotating stars between 130 and 300 solar masses and for interacting binaries from 10 to 20 solar masses. Surveying a large number of stars is necessary to explore the sensitivity of the results to uncertain explosion parameters and to give the user a library from which to select various choices of explosion energy, stellar initial mass function, mass cut, rotation rate, and mixing. Stars in the lighter mass range may make common supernovae like the Crab, but have a novel explosion mechanism and contribute little to nucleosynthesis. Stars in the upper mass range encroach on the electron-positron pair instability after helium burning and may produce multiple, supernova-like outbursts that can be highly luminous. Multidimensional simulations of mixing and fall back and calculations of shock breakout, light curves and spectra will be carried out in a representative sample of all these models.Dr. Woosley's models are used as input by many other astrophysicists studying the evolution of galaxies, how supernovae explode, the nature of gamma-ray bursts, and the origin of neutron stars and black holes. They have previously circulated most of their models and results freely, even prior to publication, and will do so under this award. Their results and graphics are frequently used by the public media, recent examples being National Geographic Magazine, Sky and Telescope, Science News, and TV documentaries by Nova, the BBC and National Geographic. The work will also include graduate student training and international collaboration.

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。伍斯利博士将继续他对元素起源和恒星演化终点的广泛研究。这包括大质量恒星（质量约为8个太阳质量）在其生命的各个阶段的演化，模拟它们的爆炸和超新星的外观，计算所有元素同位素的详细生产，并检查它们留下的中子星和黑洞的特性。将完成一项涉及大量模范星的大型调查，并向社会公布调查结果。一个有限范围的模型也将用于130到300个太阳质量的旋转恒星和10到20个太阳质量的相互作用的双星。测量大量恒星是必要的，以探索结果对不确定爆炸参数的敏感性，并为用户提供一个库，从中选择各种爆炸能量，恒星初始质量函数，质量切割，旋转速率和混合。质量较轻的恒星可能会产生像蟹状星云这样的普通超新星，但它们有一种新的爆炸机制，对核合成的贡献很小。在氦燃烧后，高质量范围内的恒星侵蚀了电子-正电子对的不稳定性，并可能产生多次类似超新星的爆发，这些爆发可能会非常明亮。将在所有这些模型的代表性样本中进行混合和后退的多维模拟以及冲击爆发、光曲线和光谱的计算。伍斯利的模型被许多其他天体物理学家用来研究星系的演化、超新星如何爆炸、伽马射线爆发的本质以及中子星和黑洞的起源。他们之前已经自由传播了他们的大部分模型和结果，甚至在发表之前，他们将在这个奖项下这样做。他们的结果和图表经常被公共媒体使用，最近的例子是《国家地理杂志》、《天空与望远镜》、《科学新闻》，以及Nova、BBC和《国家地理》的电视纪录片。这项工作还将包括研究生培训和国际合作。