Exploring the Impact of Substellar Objects on Late Stellar Evolution

探索次恒星天体对晚期恒星演化的影响

• 批准号: 1812874
• 负责人: Brad Barlow
• 金额: $ 34.96万
• 依托单位: High Point University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-08-31 至 2024-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1812874&HistoricalAwards=false
• 关键词: Exploring; Impact; Substellar; Objects; Late

Recently, planets and brown dwarfs (objects intermediate in size between planets and stars) have been discovered around very old stars that have ejected most of their material, leaving a small hot star known as a "subdwarf B" (sdB). Prior to ejecting material, the sdB stars were large red giant stars. Thus, their planets and brown dwarfs must have been engulfed as the red giant star expanded. The PI plans to use small telescopes to search for more of these sdB stars and determine whether they have companion planets or brown dwarfs. He will determine the masses of the stars and their companions, and compare the new data set with theories for how stars change near the end of their lifetimes. He will establish an integrated research and education program that will, first, teach university students to observe with robotic telescopes. The students will then teach high school teachers and students to use the telescopes to discover and analyze sdB stars. This will strengthen the students' interest and active participation in STEM research.Finding the companion masses in a large number of post-common envelope sdB binaries will provide the first robust tests of models involving red giant-engulfed companion interactions. The lower mass limits resulting from this work will help constrain model parameters relating to tidal effects and angular momentum conservation. Determination of orbital periods, eccentricities, and component masses will provide constraints on hot subdwarf formation models and improve understanding of this stage of stellar evolution. The PI, through collaborations with other astronomers, has access to Evryscope data, SKYNET, and the SOAR/Goodman telescopes.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.

最近，在非常古老的恒星周围发现了行星和褐矮星（大小介于行星和恒星之间的物体），这些恒星已经喷射出大部分物质，留下一颗被称为“亚矮星B”（sdB）的小热星星。在喷射物质之前，sdB星是大型红巨星。因此，它们的行星和褐矮星一定是在红巨星星星膨胀时被吞没的。PI计划使用小型望远镜搜索更多的sdB恒星，并确定它们是否有伴星或棕矮星。他将确定恒星及其伴星的质量，并将新的数据集与恒星在生命末期如何变化的理论进行比较。他将建立一个综合的研究和教育计划，首先，教大学生用机器人望远镜观察。然后，学生们将教高中教师和学生使用望远镜发现和分析sdB恒星。这将加强学生们对STEM研究的兴趣和积极参与。在大量的后共包络sdB双星中找到伴星质量将为涉及红巨星吞噬伴星相互作用的模型提供第一个可靠的测试。这项工作产生的较低的质量限制将有助于约束与潮汐效应和角动量守恒有关的模型参数。确定轨道周期，偏心率，和组件的质量将提供热亚矮星形成模型的约束，并提高对这一阶段的恒星演化的理解。通过与其他天文学家的合作，PI可以访问Evryscope数据、SKYNET和SOAR/Goodman望远镜。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

New Hot Subdwarf Variables from Gaia eDR3

Gaia eDR3 的新热亚矮星变量

• 发表时间: 2023
• 期刊: Bulletin de la Société royale des sciences de Liège
• 作者: Lopez, Isaac D.;Kosakowski, Alekzander;Barlow, Brad N.;Kupfer, Thomas
• 通讯作者: Kupfer, Thomas

EVR-CB-004: An Inflated Hot Subdwarf O Star + Unseen WD Companion in a Compact Binary Discovered with the Evryscope

• DOI: 10.3847/1538-4357/abb5b2
• 发表时间: 2020-09
• 期刊: The Astrophysical Journal
• 作者: J. Ratzloff;T. Kupfer;B. Barlow;D. Schneider;T. Marsh;U. Heber;Kyle A. Corcoran;E. Bauer;S. Hämmerich;H. Corbett;A. Glazier;W. Howard;N. Law

EVR-CB-001: An Evolving, Progenitor, White Dwarf Compact Binary Discovered with the Evryscope

• DOI: 10.3847/1538-4357/ab3727
• 发表时间: 2019-09
• 期刊: The Astrophysical Journal
• 作者: J. Ratzloff;B. Barlow;T. Kupfer;Kyle A. Corcoran;S. Geier;E. Bauer;H. Corbett;W. Howard

Hot Subdwarf All Southern Sky Fast Transit Survey with the Evryscope

• DOI: 10.3847/1538-4357/ab64f3
• 发表时间: 2019-12
• 期刊: The Astrophysical Journal
• 作者: J. Ratzloff;B. Barlow;P. Németh;H. Corbett;Stephen Walser;N. Galliher;A. Glazier;W. Howard

Towards a consistent model of the hot quadruple system HD 93206 = QZ Carinæ: I. Observations and their initial analyses

走向热四联系统的一致模型 HD 93206 = QZ Cariné：I. 观察及其初步分析

• DOI: 10.1051/0004-6361/202142108
• 发表时间: 2022
• 期刊: Astronomy & Astrophysics
• 影响因子: 6.5
• 作者: Mayer, P.;Harmanec, P.;Zasche, P.;Brož, M.;Catalan-Hurtado, R.;Barlow, B. N.;Frondorf, W.;Wolf, M.;Drechsel, H.;Chini, R.
• 通讯作者: Chini, R.