LEAPS-MPS:High Resolution Studies of Interacting Binaries

该奖项全部或部分根据2021年美国救援计划法案（公法117-2）资助。共生星是一种相互作用的双星系统，由红巨星通过风和/或罗奇叶溢出向白色矮星或中子星星伴星提供物质组成。它们为双星系统中的恒星演化以及包含中子星和/或黑洞的双星的形成提供了重要的见解，并且被认为贡献了Ia型超新星的一个不可忽视的部分，这是目前测量宇宙距离和宇宙加速度的最佳手段。确定质量传递的方法和速率是回答关于它们的进化和作为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，以观察质量向白色矮星/中子星星伴星的转移。迄今为止，很少有共生恒星的干涉研究，拟议的工作有望通过系统地获得任何星星（除太阳外）在多年时间轴上的一些最高分辨率图像，对该领域作出重大贡献。该项目将为硕士论文提供材料，并为服务不足的学生群体提供研究指导，并将支持对当地学校的推广活动。PI将使用高角分辨率天文学中心（CHARA）阵列上的MIRC-X（H波段和J波段），MYSTIC（K波段）和SPICA（光学）组合器来收集光学干涉数据，用于这些系统的图像重建。为了寻找质量转移的证据，他们需要在不同的轨道位置观察这些系统。因此，将在赠款期间定期收集这些数据，收集的节奏取决于每个系统的轨道参数。具有角直径大于2毫角秒的主星的系统将用于促进成像和搜索由于罗奇瓣溢出而引起的伸长。为了确定初级的基本参数和确定尘埃的存在，将使用诸如美国航天局红外望远镜设施（IRTF）上的SpeX等设施来获得近红外光谱。该提案将利用图像重建方面的进展来提高使用这些数据生成的图像的质量。新的建模技术也将被开发，以寻找系统中的伸长和盘形成。该奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

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.