BRIdging Disciplines of Galactic Chemical Evolution (BRIDGCE) Consortium 2021-2024

银河化学演化桥接学科 (BRIDGCE) 联盟 2021-2024

• 批准号: ST/V000462/1
• 负责人: Alexander Murphy
• 金额: $ 2.88万
• 依托单位: University of Edinburgh
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=ST%2FV000462%2F1
• 关键词: BRIdging; Disciplines; Galactic; Chemical; Evolution

"How did the Universe begin and evolve" is one of the three science challenges identified in the STFC Astronomy Programme. We address this question by modelling physical processes from the micro (nuclear, stellar) to the macro scales (galactic, cosmological), studying the ionising and chemical feedback from stars and the wider context of galaxy formation.The BRIDGCE consortium is a multidisciplinary collaboration between nuclear, stellar and extra-galactic astrophysicists, which aims to achieve a comprehensive understanding of the evolution of the Universe from the era of reionisation up to now, using chemical elements as fingerprints of the physical processes that occur in stars and galaxies. Elements heavier than helium are produced in stars and supernovae on different timescales, and the stellar populations and interstellar medium within galaxies keep a record of star formation and chemical enrichment histories of galaxies. Therefore, it is also possible to constrain galaxy formation theory from the observed elemental abundances, and to do this more accurately we need to understand stellar and nuclear Astrophysics. Moreover, the discovery of gravitational waves (GW) has opened a new window to the Universe, allowing us to observe the formation of black holes and neutron stars more directly than ever before. GWs can provide independent new constraints on stellar winds, evolution, and stellar deaths via black hole remnants, and the seeds of super-massive black holes in galaxies.The development of high-performance computing enables us to study the theory of stars and galaxies self-consistently: we simulate how stars lose mass via stellar winds prior to supernovae explosions (Project-1); we simulate the full evolution of stars in one-dimension (1D) and compute 3D scans of their interiors (Project-2). Furthermore, by combining stellar evolution and nucleosynthesis to galactic dynamical evolution, we reproduce the entire chemodynamical history of local dwarf galaxies (Project-3) and of the Milky Way (Project-4). Our research addresses some of the key questions of 21st century Astronomy: How black holes and neutron stars are formed (Projects 1 & 2)?, How many GW events will be detected in future missions?, and How we can trace the evolution of the Universe from GWs (Project-5)?Nuclear data (nuclear reaction rates in particular) are a key input for stellar evolution models since nuclear reactions provide the energy that powers stars. This information determines stellar lifetimes and the composition of their ejecta. Stars provide important feedback into galaxies through the light they radiate, their powerful winds and explosions, and all the chemical elements they produce. The outputs of stellar models are thus key ingredients for galactic chemical evolution models. These models follow successive episodes of star formation and trace the history of the enrichment of the elements. The model predictions can then be compared to observations of stars, stellar populations, and the inter-stellar medium that carries the chemical fingerprints of the cumulative chemical enrichment that preceded their birth. Comparison to observations can thus constrain both the galactic and stellar properties. Finally, most stars are not born on their own, but may instead evolve interacting with a companion. Although this has been known for decades, the impact of binarity on galaxy evolution is poorly known.In the BRIDGCE 2021-2024 grant, our galaxy experts will explore this new scientific problem together with our stellar experts. Our consortium project applies innovative techniques across different disciplines and tackles this challenge through 5 projects corresponding to very different physical scales: stellar envelopes (Project-1), stellar cores (Project-2), local dwarf galaxies (Project-3), the Milky Way (Project-4), and the Universe as a whole (Project-5). These impact many areas of Astrophysics as well as Cosmology & Nuclear Physics.

“宇宙是如何开始和演化的”是 STFC 天文学计划确定的三大科学挑战之一。我们通过对从微观（核、恒星）到宏观（银河、宇宙）尺度的物理过程进行建模，研究恒星的电离和化学反馈以及星系形成的更广泛背景来解决这个问题。BRIDGCE联盟是核、恒星和银河系外天体物理学家之间的多学科合作，旨在全面了解自宇宙时代以来的宇宙演化。 迄今为止的再电离，使用化学元素作为恒星和星系中发生的物理过程的指纹。比氦重的元素在不同时间尺度的恒星和超新星中产生，星系内的恒星族和星际介质记录着星系的恒星形成和化学富集历史。因此，也有可能根据观测到的元素丰度来约束星系形成理论，为了更准确地做到这一点，我们需要了解恒星和核天体物理学。而且，引力波（GW）的发现为宇宙打开了一扇新的窗口，使我们能够比以往更直接地观察黑洞和中子星的形成。引力波可以通过黑洞残骸和星系中超大质量黑洞的种子，为恒星风、演化和恒星死亡提供独立的新约束。高性能计算的发展使我们能够自洽地研究恒星和星系的理论：我们模拟超新星爆炸之前恒星如何通过恒星风失去质量（Project-1）；我们在一维 (1D) 中模拟恒星的完整演化，并计算其内部的 3D 扫描 (Project-2)。此外，通过将恒星演化和核合成与星系动力学演化相结合，我们重现了当地矮星系（Project-3）和银河系（Project-4）的整个化学动力学历史。我们的研究解决了 21 世纪天文学的一些关键问题：黑洞和中子星是如何形成的（项目 1 和 2）？在未来的任务中将检测到多少引力波事件？以及我们如何从引力波中追踪宇宙的演化（项目 5）？核数据（特别是核反应速率）是恒星演化模型的关键输入，因为核反应提供了为恒星提供能量的能量。这些信息决定了恒星的寿命及其喷射物的成分。恒星通过它们辐射的光、强大的风和爆炸以及它们产生的所有化学元素向星系提供重要的反馈。因此，恒星模型的输出是星系化学演化模型的关键成分。这些模型遵循恒星形成的连续事件，并追踪元素富集的历史。然后，可以将模型预测与对恒星、恒星种群和星际介质的观测进行比较，这些介质携带着恒星诞生前累积化学富集的化学指纹。因此，与观测结果的比较可以限制星系和恒星的特性。最后，大多数恒星并不是自己诞生的，而是可能在与同伴的相互作用中进化而来。尽管这一点几十年前就已为人所知，但双星对星系演化的影响却鲜为人知。在 BRIDGCE 2021-2024 拨款中，我们的星系专家将与我们的恒星专家一起探索这个新的科学问题。我们的联盟项目应用了不同学科的创新技术，并通过对应于截然不同的物理尺度的 5 个项目来应对这一挑战：恒星包层 (Project-1)、恒星核心 (Project-2)、本地矮星系 (Project-3)、银河系 (Project-4) 和整个宇宙 (Project-5)。这些影响了天体物理学以及宇宙学和核物理学的许多领域。

项目成果

Realistic 3D hydrodynamics simulations find significant turbulent entrainment in massive stars

真实的 3D 流体动力学模拟发现大质量恒星中存在显着的湍流夹带

• DOI: 10.1093/mnras/stac1981
• 发表时间: 2022
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: Rizzuti F