Angular Momentum Destinies of Massive Stars

该奖项将支持一项观测计划，以表征大质量恒星的基本特性。吉斯博士和他的团队将通过光学干涉测量法对附近大质量恒星的直径和平坦度进行观测。该项目的第一部分将确定大质量恒星样本的温度、半径、质量和旋转速度。转速将通过干涉测量旋转平坦度和光谱测量与旋转有关的多普勒频移来估计。该项目的第二部分将研究大质量双星如何随着时间的推移相互作用，交换质量和角动量。该项目的观测将使用位于加州威尔逊山的高分辨率天文中心（CHARA）望远镜阵列进行。该项目预计将影响更广泛的恒星天体物理学领域，因为观测结果将为大质量恒星从青年到老年的旋转演化提供关键的理论模型测试。该项目还将涉及佐治亚州立大学（GSU）的研究生，该研究的结果将纳入该机构的本科课程。PI还建议与威尔逊山天文台和乔治亚州州立大学艰苦劳动溪天文台协调开展教育和外展活动。

This award will support an observational program to characterize the fundamental properties of massive stars. Dr. Gies and his team will conduct observations of the diameters and flattening of nearby massive stars, obtained with optical interferometry. The first part of this project will determine temperatures, radii, masses, and rotational velocities for a large sample of massive stars. The rotational speeds will be estimated through interferometric measurements of rotational flattening and spectroscopic measurements of the Doppler shifts related to rotation. The second part of the project will examine how close pairs of massive binary stars interact over time exchanging both mass and angular momentum. The observations for this project will be conducted using the Center for High Resolution Astronomy (CHARA) telescope array, located at Mt. Wilson, California. The project is expected to impact the wider field of stellar astrophysics because the observations will provide key tests of theoretical models for the rotational evolution of massive stars from youth to old age. The project will also involve graduate students at Georgia State University (GSU), and the results from this research will be incorporated into that institution's undergraduate curriculum. The PI also proposes to engage in education and outreach activities in coordination with the Mount Wilson Observatory, and the GSU Hard Labor Creek Observatory in Georgia.