Collaborative Research: White Dwarfs in Binaries Across the H-R Diagram with the APOGEE-GALEX-Gaia Catalog

超过95%的恒星最终将以白矮星的形式结束--白矮星的残骸已经耗尽了它们的核燃料，并坍塌到与地球相当的大小，但质量与太阳相当。这些白矮星中的许多都被锁定在与恒星同伴的宇宙舞蹈中，在那里它们相互环绕并交换质量。如此近距离的白矮星双星系统为研究恒星演化的后期阶段提供了极好的机会。它们还可以用作银河系动力学的示踪器，它们也是引力波的潜在来源。这个项目的目标是收集这些系统在广泛波长范围内的数据，以确定它们的特征，并调查它们的基本性质，如它们的组成和它们共享的质量。这项工作还将为不同阶段的理科学生提供几个项目，调查人员将与无障碍专家合作，创建培训计划，向盲人和视障人士教授天文学。大多数白矮星居住在多个系统中，其中很大一部分足够致密，可以交换质量，改变了两颗恒星的结构和随后的演化。调节这些质量交换的物理机制包括共同包层演化、罗氏叶溢出、风吸积、质量剥离和恒星合并。这项提议的主要目的是通过收集数以千计的质量转移后双星的独特观测样本来加深我们对相互作用系统中质量转移过程的理解。源样本将GALEX和GAIA数据库与远地点--高分辨率(R=22,500)、高信噪比、多历元、红外线(1.51μm到1.69μm)--相结合，对整个银河系的恒星进行光谱观测，以建立对质量转移后双星最详尽的调查，其中包含主序列、亚巨星、红巨星和红团伴星。这个远地点-GALEX-GAIA星表的创建和对结果数据集的拟议分析将提高我们对包含白矮星的质量转移后双星种群的了解，并绘制出它们的性质随着非简并恒星的演化而发生的变化。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

More than 95 percent of stars will eventually end up as white dwarfs - the remains of stars that have used up their nuclear fuel and collapsed to a size equivalent to Earth but with a mass comparable to the Sun. Many of these white dwarfs are locked in a cosmic dance with stellar companions, where they orbit around each other and exchange mass. Such close white dwarf binary systems offer an excellent opportunity to study the late stages of stellar evolution. They can also be used as tracers of the dynamics of the Milky Way galaxy, and they are potential sources of gravitational waves. The goal of this project is to collect data on these systems at a wide range of wavelengths to characterize them and investigate fundamental properties, like what they are made of and how much mass they are sharing. This work will also provide several projects for science students at various stages, and the investigators will work with experts in accessibility to create training programs to teach astronomy to blind and visually impaired people. Most white dwarfs inhabit multiple systems, and a large fraction of those are compact enough to exchange mass, changing the structures and subsequent evolution of both stars. The physical mechanisms that mediate these mass exchanges include common envelope evolution, Roche lobe overflow, wind accretion, mass stripping, and stellar mergers. The main goal of this proposal is to further our understanding of mass transfer processes in interacting systems by assembling a unique observational sample of thousands of post mass-transfer binaries. The source sample combines the GALEX and Gaia databases with APOGEE — a high resolution (R=22,500), high signal-to-noise, multi-epoch, infrared (1.51 μm to 1.69 μm), spectroscopic survey of stars across the Milky Way — to build the most exhaustive survey of post-mass transfer binaries, containing systems with main sequence, subgiant, red giant, and red clump companions. The creation of this APOGEE-GALEX-Gaia Catalog and the proposed analysis of the resulting data set will improve our knowledge of the population of post-mass transfer binaries containing a white dwarf, and map the changes in their properties as a function of the evolution of the non-degenerate companion.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.