LEAPS-MPS:High Resolution Studies of Interacting Binaries

该奖项全部或部分由《2021年美国救援计划法案》（公法117-2）资助。共生恒星是一种相互作用的双星系统，由一颗红巨星组成，它通过风和/或罗氏叶溢出向白矮星或中子星伴侣捐赠物质。它们对双星系统的恒星演化和包含中子星和/或黑洞的双星的形成提供了重要的见解，并且被认为是Ia型超新星的重要组成部分，Ia型超新星目前为我们提供了测量宇宙距离和宇宙加速度的最佳手段。确定传质方法和传质速率是回答有关它们的进化和作为Ia型祖细胞的作用的问题的关键。首席研究员（PI）将带领一组学生使用光学干涉测量法测量已知共生恒星样本中红巨星的精确形状和半径，以观察质量向白矮星/中子星伴星的转移。迄今为止，对共生恒星进行的干涉测量研究很少，而这项提议的工作有望在多年的时间内系统地获得任何恒星（除了太阳）的一些最高分辨率的图像，从而对该领域做出重大贡献。该项目将为缺乏服务的学生群体提供硕士论文材料和研究指导，并将支持向当地学校推广的举措。PI将使用高角分辨率天文中心（CHARA）阵列上的MIRC-X （h波段和j波段）、MYSTIC （k波段）和SPICA（光学）组合器收集光学干涉数据，用于这些系统的图像重建。为了寻找质量传递的证据，他们需要在不同的轨道位置观察这些系统。因此，这些数据将在拨款过程中定期收集，其节奏取决于每个系统的轨道参数。主星角直径大于2毫弧秒的系统将被用来促进成像和搜索由于罗氏叶溢出引起的延伸。为了确定原星的基本参数并确定尘埃的存在，NASA红外望远镜设施（IRTF）上的SpeX等设备将被用来获得近红外光谱。该提案将利用图像重建方面的先进技术来提高使用这些数据生成的图像的质量。还将开发新的建模技术，以搜索系统中的延伸和磁盘形成。该奖项反映了美国国家科学基金会的法定使命，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。

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2). Symbiotic stars are a type of interacting binary system consisting of a red giant that donates material to a white dwarf or neutron star companion via winds and/or Roche-lobe overflow. They offer important insights into stellar evolution in binary systems and the formation of binaries containing neutron stars and/or black holes, and are believed to contribute a not- insignificant fraction of Type Ia supernovae, which currently provide our best means of measuring cosmic distances and the acceleration of the universe. Determining the method and rate of mass transfer is key to answering questions about their evolution and role as Type Ia progenitors. The principal investigator (PI) will lead a team of students using optical interferometry to measure precise shapes and radii of the red giant stars in a sample of known symbiotic stars to observe the transfer of mass to the white dwarf/neutron star companion. Few interferometric studies of symbiotic stars have been done to date, and the proposed work promises to make a significant contribution to the field by systematically obtaining some of the highest resolution images of any star (apart from the sun) over a multi-year timeline. The project will provide material for a Master’s Thesis and research mentoring for underserved student populations and will support outreach initiatives to local schools.The PI will use the MIRC-X (H-band and J-band), MYSTIC (K-band), and SPICA (optical) combiners on the Center for High Angular Resolution Astronomy (CHARA) Array to collect optical interferometric data for image reconstruction of these systems. In order to look for evidence of mass transfer, they will need to observe these systems at different orbital positions. As a result, these data will be collected regularly over the course of the grant, with cadence depending on the orbital parameters of each system. Systems with primary stars of angular diameter greater than 2 milli-arcseconds will be used to facilitate imaging and search for elongation due to Roche-lobe overflow. In order to determine the fundamental parameters of the primary and identify the presence of dust, facilities such as SpeX on the NASA InfraRed Telescope Facility (IRTF) will be used to obtain near-infrared spectroscopy. The proposal will use advances in image reconstruction to improve the quality of images produced using the data. New modelling techniques will also be developed to search for elongation and disk formation in the systems.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.