Asteroseismic analyses of the physics red-giant interiors

物理红巨星内部的星震分析

• 批准号: 2205026
• 负责人: Sarbani Basu
• 金额: $ 44.91万
• 依托单位: Yale University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-01 至 2025-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2205026&HistoricalAwards=false
• 关键词: Asteroseismic; analyses; physics; red; giant

The study of stars is of paramount importance in astrophysics: almost all investigations of our Galaxy and other galaxies are done through the observation of starlight. Properties of stars in our Galaxy — their chemical abundances, ages, and dynamics — are used to study its chemical and dynamical evolution. While chemical abundances can be obtained from spectroscopy and dynamical properties can be measured by specialized observations such as those provided by satellites like Gaia, ages are much more complicated, because they are model dependent. Using a cutting-edge technique called asteroseismology, the study of the seismic behavior of stars, and combining both observational and theoretical methods, this project will significantly improve and enhance the basic theory of stellar structure and evolution by clarifying some of the most important physical processes that take place deep within stars. In turn, this will make stellar properties, including age estimates, more precise. The results will also allow better calibration of the relation between stellar ages and the abundance of various elements. The project is enriched by an ambitious outreach program based on public lectures, workshops, and summer internships, three components of a scaffolded approach aimed at increasing participation in STEMS for young students and supporting their transition to college. The plan is supported by, and is part of, the well-established and successful “Yale Pathways to Science” program. The project will focus on evolved stars, subgiants and red giants, the ages of which are vital in studying the chemo-dynamical evolution of the Galaxy. The primary goal is to examine the mixing processes, such as overshoot and turbulent mixing, that affect red giant structures, using the individual asteroseismic frequencies and period spacings of these stars. The first part of the project is a theoretical study of the observable seismic signatures produced by different mixing processes; the second is a seismic study of evolved stars with asteroseismic data from Kepler to examine what are the processes that actually take place in stars.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

对恒星的研究在天体物理学中至关重要：几乎所有对银河系和其他星系的研究都是通过对星光的观测来完成的。 我们银河系中恒星的性质--它们的化学丰度、年龄和动力学--被用来研究它的化学和动力学演化。虽然化学丰度可以从光谱学中获得，动力学性质可以通过专门的观测来测量，例如盖亚等卫星提供的观测，但年龄要复杂得多，因为它们依赖于模型。该项目利用称为星震学的尖端技术，即研究恒星的地震行为，并结合观测和理论方法，通过澄清恒星内部深处发生的一些最重要的物理过程，将大大改进和加强恒星结构和演化的基本理论。反过来，这将使恒星的性质，包括年龄估计，更加精确。这些结果也将允许更好地校准恒星年龄和各种元素丰度之间的关系。该项目通过一个雄心勃勃的外展计划来丰富，该计划基于公开讲座，研讨会和暑期实习，这是一种脚手架方法的三个组成部分，旨在增加年轻学生对STEMS的参与，并支持他们向大学过渡。该计划是由支持，是一部分，完善和成功的“耶鲁大学科学之路”计划。 该项目将侧重于演化恒星、亚巨星和红巨星，其年龄对于研究银河系的化学动力演化至关重要。主要目标是研究混合过程，如过冲和湍流混合，影响红巨星的结构，使用这些恒星的单个小行星地震频率和周期间隔。该项目的第一部分是对不同混合过程产生的可观测地震特征进行理论研究;第二个奖项是利用开普勒的星震数据对演化恒星进行地震研究，以检查恒星中实际发生的过程。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Evolutionary and Observational Properties of Red Giant Acoustic Glitch Signatures

红巨星声学毛刺特征的演化和观测特性

• DOI: 10.3847/1538-4357/acbdf3
• 发表时间: 2023
• 期刊: The Astrophysical Journal
• 作者: Saunders, David P.;Ong 王, J. M. Joel 加冕;Basu, Sarbani
• 通讯作者: Basu, Sarbani