Stellar Atmospheres in the Laboratory: A Testbed for Fundamental Atomic Processes

实验室中的恒星大气：基本原子过程的试验台

• 批准号: 1707419
• 负责人: Donald Winget
• 金额: $ 45万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1707419&HistoricalAwards=false
• 关键词: Stellar; Atmospheres; Laboratory; Testbed; Fundamental

Most stars---including our Sun---will end their lives as white dwarf stars, which no longer undergo nuclear fusion. Understanding white dwarf stars is an important tool for astronomy because these stars can serve as cosmic clocks that probe the age and history of the universe. This research project will create in the laboratory conditions that are similar to those found on the surfaces of white dwarf stars. A detailed analysis of the light absorbed and emitted by atoms under such conditions will allow astronomers to better understand white dwarf stars. This project will train graduate students in sophisticated laboratory techniques, and it will support science outreach to local high schools.The research team will conduct new laboratory measurements that will provide key benchmarks for atomic line broadening observed in white dwarf stars. They will make these measurements using an experiment that they have built for the Z-machine at Sandia National Laboratories. The experiment is capable of producing hydrogen, helium, and carbon plasmas that are similar to those in white dwarf photospheres. Accurate atomic spectral line parameters measured in these laboratory plasmas would allow astronomers to accurately diagnose plasma conditions at the surfaces of white dwarf stars and test theories of line broadening there. White dwarf stars could then be used to constrain the age and history of the Galactic disk, Galactic halo, and individual stellar clusters, and as astrophysical laboratories in which to study the fundamental physics of crystallization, phase separation, diffusion, and plasmon neutrino emission. This project will train graduate students in the methods and applications of laboratory astrophysics, and it will provide opportunities to undergraduate students from the Freshman Research Initiative program at UT Austin.

大多数恒星--包括我们的太阳--将以白色矮星的形式结束它们的生命，不再进行核聚变。 了解白色矮星是天文学的重要工具，因为这些恒星可以作为宇宙时钟，探测宇宙的年龄和历史。 该研究项目将在实验室中创造与白色矮星表面相似的条件。 对原子在这种条件下吸收和发射的光进行详细分析，将使天文学家更好地了解白色矮星。 该项目将培训研究生掌握先进的实验室技术，并将支持向当地高中推广科学，研究小组将进行新的实验室测量，为在白色矮星上观察到的原子谱线加宽提供关键基准。 他们将使用他们在桑迪亚国家实验室为Z机建造的实验来进行这些测量。 该实验能够产生类似于白色矮星光球中的氢、氦和碳等离子体。 在这些实验室等离子体中测量的精确原子光谱线参数将使天文学家能够准确诊断白色矮星表面的等离子体条件，并测试那里的谱线加宽理论。 然后，白色矮星可以用来限制银河系盘、银河系晕和单个星团的年龄和历史，并作为天体物理实验室，研究结晶、相分离、扩散和等离子体中微子发射的基础物理。 该项目将培养研究生在实验室天体物理学的方法和应用，它将提供机会，从UT奥斯汀的新生研究计划的本科生。

项目成果

Limits on Mode Coherence in Pulsating DA White Dwarfs Due to a Nonstatic Convection Zone

• DOI: 10.3847/1538-4357/ab6a0e
• 发表时间: 2020-01
• 期刊: The Astrophysical Journal
• 作者: M. Montgomery;J. Hermes;D. Winget;B. Dunlap;K. Bell

Kepler and TESS Observations of PG 1159-035

• DOI: 10.3847/1538-4357/ac8871
• 发表时间: 2022-08
• 期刊: The Astrophysical Journal
• 作者: Gabriela Oliveira da Rosa;S. O. Kepler;A. H. C'orsico;J. E. S. Costa;J. Hermes;S. Kawaler;K. Bell;M. Montgomery;J. Provencal;D. Winget;G. Handler;B. Dunlap;J. Clemens;M. Uzundag

Identifying Periodic Variable Stars and Eclipsing Binary Systems with Long-term Las Cumbres Observatory Photometric Monitoring of ZTF J0139+5245

• DOI: 10.3847/1538-3881/ac18be
• 发表时间: 2021-07
• 期刊: The Astronomical Journal
• 作者: A. Sanghi;Z. Vanderbosch;M. Montgomery

Matrix Methods for Solving Hartree-Fock Equations in Atomic Structure Calculations and Line Broadening

求解原子结构计算和谱线展宽中 Hartree-Fock 方程的矩阵方法

• DOI: 10.3390/atoms6020022
• 发表时间: 2018
• 期刊: Atoms
• 影响因子: 1.8
• 作者: Gomez, Thomas;Nagayama, Taisuke;Fontes, Chris;Kilcrease, Dave;Hansen, Stephanie;Montgomery, Mike;Winget, Don
• 通讯作者: Winget, Don

An Effort to Reconcile Electron-Broadening Theories

协调电子展宽理论的努力

• 发表时间: 2019
• 期刊: International Conference on Atomic Processes in Plasmas
• 作者: Gomez, T. A.;Nagayama, T.;Fones, C. J.;Kilcrease, D. P.;Montgomery, M. H.;Winget, D. E.
• 通讯作者: Winget, D. E.