Supernova Progenitors, Stellar Remnants, and their Binary Companions

在过去的十年里，双星系统的研究重新引起了人们的关注，因为它们被证明在广泛的天文学领域中发挥着关键作用：X射线和脉冲星双星、伽马射线爆发、太阳系外行星、引力波来源、超新星(SN)前体、宇宙学，特别是瞬变天文学。观测上的进步改变了格局，并突显了当前建模尝试的局限性。与此同时，在过去的十年中，双星进化模型并没有取得重大进展；反过来，这限制了我们理解和解释目前与双星种群相关的一些观测结果的能力。在过去经验的基础上，该项目的研究人员将推进双星建模和紧凑天体形成和演化的物理复杂性。他们将开发下一代双种群模拟工具(PSyDLib)，该工具具有自洽物理建模的主要关键优势。该团队将利用计算能力的持续增长和MESA的公开可获得性，MESA是一种多功能、健壮的恒星结构和演化代码。所有的模拟代码将公开用于其他研究项目。这个项目将利用PI与当地学校(芝加哥地区的城市和郊区)建立的联系，以前/现在与高中教师的工作，以及天文学对儿童的吸引力，以满足小学和中学水平的STEM教育的关键需求。在所有学校一级，目前正在实施的“下一代科学标准”要求引入和使用计算思维和建模。然而，在这一领域，大多数学校教师没有专业知识，没有表达他们对专业发展和适当课程材料的需求。国际天文学协会将与经验丰富的教师小组合作，开发计算天文学课程材料。PI还将利用过去在天文学可视化方面的工作，并为双星和X射线双星形成中的质量传递开发新的工作。PI将在芝加哥阿德勒天文馆和埃文斯顿高中新天文馆的公共宣传演示中广泛使用它们。PI还将涉及两名女性研究生，她们将接受高级计算方面的培训，因此将为一支多样化的、具有全球竞争力的STEM工作队伍做出贡献。更技术上，该团队将开发新的模块和创新的混合软件结构，以纳入(I)真实的质量转移序列和稳定性的物理评估，(Ii)对共同包络演化的高级处理，消除对特别参数化的需要，以及(Iii)针对潮汐和质量转移引起的偏心、异步双星的一般情况下的自洽轨道演化。该项目的科学目标侧重于研究(I)核心坍塌超新星的前身及其双星的物理性质，并与超新星观测结果进行比较，以及(Ii)银河系和麦哲伦星云中的高质量X射线双星，这提供了大量与最初预期截然不同的观测系统。考虑到更多的XRB样本，研究人员实际上将使用(Ii)中的比较来校准他们的模型，并评估(I)预测的可靠性。预期的结果不仅有助于解释目前的观测结果，还将为未来的多波长观测提供动力和预测。

The study of binary stellar systems has attracted renewed attention in the past decade as they are shown to play a critical role in a wide range of astronomy areas: X-ray and pulsar binaries, gamma-ray bursts, extrasolar planets, gravitational-wave sources, supernova (SN) progenitors, cosmology, and especially transient astronomy. Observational advances have transformed the landscape and have highlighted the limitations of current modeling attempts. At the same time binary evolution modeling has not advanced significantly in the past decade; in turn, this has limited our ability to understand and interpret a number of current observational results related to binary populations. Building on their past experience, the investigators in this project will advance the physical sophistication of binary modeling and compact object formation and evolution. They will develop the next-generation binary-populations simulation tool (PSyDLib) with major, key advantages for self-consistent, physical modeling. The team will take advantage of the continued increase in computational power and the public availability of MESA, a versatile, robust stellar structure and evolution code. All the simulation codes will be made publicly available for other research projects.This project will take advantage of the PI's established connections with local schools (urban and suburban in the Chicago area), prior/current work with high-school teachers, and astronomy's appeal to children to address a critical need in elementary- and middle-school level STEM education. At all school levels the Next Generation Science Standards that are currently being implemented call for the introduction and use of computational thinking and modeling. However, in this area most school teachers do not have expertise and voice their need for professional development and appropriate curriculum materials. In collaboration with small teams of experienced teachers, the PI will develop computational astronomy curriculum materials. The PI will also capitalize on past work on astronomy visualizations and develop new ones for mass transfer in binaries and X-ray binary formation. The PI will use them extensively at public outreach presentations at Chicago's Adler Planetarium and the Evanston High School new planetarium. The PI will also involve two female graduate students who will be trained in advanced computation, hence contributing to a diverse, globally competitive STEM workforce.More technically, the team will develop new modules and an innovative hybrid software structure to incorporate (i) realistic mass-transfer sequences and physical assessment of stability, (ii) advanced treatment of common-envelope evolution eliminating the need for ad-hoc parameterization, and (iii) self-consistent orbital evolution for the general case of eccentric, asynchronous binaries due to tides and mass transfer. The project's science goals focus on studies of (i) core-collapse supernovae in terms of the physical properties of both their progenitors and their binary companions and compare to observational results from supernova surveys and (ii) high-mass X-ray binaries in the Milky Way and the Magellanic Clouds, which provide a plethora of observed systems with very different properties than originally expected. Given the more substantial XRB samples, the investigators will actually use the comparisons in (ii) to calibrate their models and assess the reliability of predictions for (i). The anticipated results will not only help to explain current observations but will also provide motivation and predictions for future multi-wavelength observations.