CAREER: Fundamental properties of young and pre-main-sequence stars

事业：年轻恒星和前主序恒星的基本特性

• 批准号: 2143763
• 负责人: Andrew Mann
• 金额: $ 63.5万
• 依托单位: University of North Carolina at Chapel Hill
• 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: 2022-04-01 至 2027-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2143763&HistoricalAwards=false
• 关键词: CAREER; Fundamental; properties; young; pre

Stars form the foundation upon which much of modern astronomy rests and directly impact sub- fields as diverse as the cosmic distance scale, galaxy structure and evolution, the synthesis of chemical elements, planet formation, and the origin of life. Precise knowledge of basic stellar parameters such as mass, radius, age, and luminosity are thus essential. However, substantial gaps in this knowledge exist for young, low-mass stars due to the paucity of known eclipsing and astrometric binary stars among this population that enable accurate determinations of these quantities. The proposed research will derive accurate luminosities, radii, ages, and masses for young, low-mass stars using binary systems recently identified by Gaia, K2, and TESS surveys. This project will also support research activities by a graduate and several undergraduate students, as well as efforts by the principal investigator to develop interactive activities for astronomy courses and an interactive/multimedia-based exhibit based on this research for the Morehead Planetarium on the UNC Chapel Hill campus.The researchers will derive stellar parameters to better than 5% accuracy for 5-500 million year old K & M stars through the analysis of light curves in a sample of low-mass eclipsing and astrometric binary systems. This is a proven method that is routinely applied to older, more massive stars. Using these systems as ``benchmarks’’ they will derive empirical mass-luminosity-age relations, investigate the impact of magnetic activity on the derived parameters, and determine empirical relations for stellar radii, luminosity, and surface temperature from direct observables given an age. They will further explore age distributions in star clusters using spectroscopically determined lithium abundances and through explicit modeling of multiple populations. A major motivation of this work is to provide improved parameters for young planetary hosts, however the derived relations between direct observables and fundamental properties will be applicable to a wide variety of scientific applications.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.

恒星构成了许多现代天文学的基础，并直接影响像宇宙距离量表，星系结构和进化，化学元素的合成，行星形成以及生命的起源一样的潜水场。因此，必不可少的基本恒星参数的精确知识，例如质量，半径，年龄和光度。然而，由于该人群中已知的黯然失色和天文二元星星的稀少，因此对于年轻的低质量恒星而存在，这一知识存在很大的差距，从而可以准确确定这些数量。拟议的研究将使用Gaia，K2和Tess Surveys最近确定的二进制系统来得出年轻的低质量恒星的准确亮度，半径，年龄和质量。该项目还将支持研究生和几位本科生的研究活动，以及首席研究人员的努力，为天文学课程开发互动活动，并根据这项研究基于这项研究的互动/基于互动/多媒体的展览，用于莫尔黑德天文馆对UNCEL Chapel Hill校园的莫尔黑德天文馆的研究。低质量蚀和天体二进制系统。这是一种经过验证的方法，通常应用于较老，更大的恒星。他们将使用这些系统作为``基准''，他们将使用光谱确定的锂丰度和通过多个种群的明确建模来进一步探索星团中的年龄分布。这项工作的一个主要动机是为年轻的行星宿主提供改进的参数，但是直接观察和基本属性之间的派生关系将适用于各种科学应用。该奖项反映了NSF的法定任务，并已通过评估该基金会的知识分子和更广泛的影响来评估NSF的法定任务，并被认为是珍贵的支持。

项目成果

Using the Gaia Excess Uncertainty as a Proxy for Stellar Variability and Age

使用盖亚过度不确定性作为恒星变率和年龄的代理

• DOI: 10.3847/1538-4357/ace044
• 发表时间: 2023
• 期刊: The Astrophysical Journal
• 作者: Barber, Madyson G.;Mann, Andrew W.
• 通讯作者: Mann, Andrew W.

A Lithium Depletion Age for the Carina Association

Carina 协会的锂耗尽时代

• DOI: 10.3847/1538-3881/ad03f3
• 发表时间: 2023
• 期刊: The Astronomical Journal
• 作者: Wood, Mackenna L.;Mann, Andrew W.;Barber, Madyson G.;Bush, Jonathan L.;Milburn, Reilly P.;Thao, Pa Chia;Schmidt, Stephen P.;Tofflemire, Benjamin M.;Kraus, Adam L.
• 通讯作者: Kraus, Adam L.

Quantifying the Transit Light Source Effect: Measurements of Spot Temperature and Coverage on the Photosphere of AU Microscopii with High-resolution Spectroscopy and Multicolor Photometry

• DOI: 10.3847/1538-4357/ad0bed
• 发表时间: 2023-10
• 期刊: The Astrophysical Journal
• 作者: W. Waalkes;Z. Berta-Thompson;Elisabeth Newton;A. Mann;Peter Gao;H. Wakeford;L. Alderson;P. Plavchan

Hazy with a Chance of Star Spots: Constraining the Atmosphere of Young Planet K2-33b

• DOI: 10.3847/1538-3881/aca07a
• 发表时间: 2022-11
• 期刊: The Astronomical Journal
• 作者: P. C. Thao;A. Mann;P. Gao;Dylan A. Owens;A. Vanderburg;E. Newton;Yao Tang;M. J. Fields;T. David;J. Irwin;T. Husser;D. Charbonneau;S. Ballard

TESS Hunt for Young and Maturing Exoplanets (THYME). IX. A 27 Myr Extended Population of Lower Centaurus Crux with a Transiting Two-planet System

• DOI: 10.3847/1538-3881/aca8fc
• 发表时间: 2022-12
• 期刊: The Astronomical Journal
• 作者: M. Wood;A. Mann;Madyson G. Barber;Jonathan L. Bush;A. Kraus;B. Tofflemire;A. Vanderburg;E. Newton;G. Feiden;G. Zhou;L. Bouma;S. Quinn;David J Armstrong;A. Osborn;V. Adibekyan;E. D. Mena;S. Sousa;Jonathan Gagn'e;M. J. Fields;Reilly P. Milburn;P. C. Thao;S. P. Schmidt;C. Gnilka;S. Howell;N. Law;C. Ziegler;C. Briceño;G. Ricker;R. Vanderspek;D. Latham;S. Seager;J. Winn;J. Jenkins;J. Schlieder;H. Osborn;J. Twicken;D. Ciardi;Chelsea X. Huang