Physics, cosmology, and exoplanetary science with the white dwarf stars

白色矮星是类似太阳的恒星在其核熔炉熄灭后形成的残余物。 在我们的银河系中有数十亿个它们，大多数除了冷却之外没有做任何有趣的事情。 然而，它们中的一些在近距离双星系统中运行，其中恒星最终螺旋在一起导致大规模爆炸，其他彗星和小行星从其行星系统中遗留下来，还有一些有“星震”，让我们可以对其内部进行地震学。 该项目将研究白色矮星的有趣例子，以了解天文学家用来测量距离的超新星爆炸，系外行星系统的组成和配置，以及密度比铅高1000万倍且无法在任何地球实验室生产或研究的材料的物理学。该计划还将促进学生在仪器开发方面的培训，并为天文学界提供新的观测能力。PI和他的研究生团队将使用白色矮星作为工具进行3个独立的调查，以研究（1）热DQ白色矮星是否是由两个亚阿布拉塞卡质量的白色矮星合并而成的，（2）富含金属的白色矮星与星周尘埃是否正在吸积行星物质，以及（3）ZZ鲸鱼座恒星的性质。共同的线索是使用SOAR望远镜和古德曼摄谱仪获得的观测结果，这是由PI建造的。在该奖项的部分支持下，PI将为光谱仪建立一个红色通道，这对观测界非常感兴趣，并将进一步推动三个关键观测计划。

White dwarfs stars are the remnants of stars like the sun that form after their nuclear furnace has gone out. There are billions of them in our galaxy and most are not doing anything interesting besides cooling off. However, some of them orbit in close binary (double-star) systems in which the stars eventually spiral together causing massive explosions, others pulverize comets and asteroids left over from their planetary systems, and still others have "starquakes" that let us conduct seismology of their interiors. This project will study interesting examples of white dwarfs to learn about the supernova explosions that astronomers use to measure distances, the composition and configuration of exoplanetary systems, and the physics of material that is 10 million times denser than lead and cannot be produced or studied in any terrestrial laboratory. This program will also facilitate student training in instrument development and provide a new observational capability for the astronomical community. The PI and his team of graduate students will carry out 3 separate investigations using white dwarfs as tools to study (1) whether hot DQ white dwarfs result from mergers of two sub-Chandrasekhar mass white dwarfs, (2) whether metal-rich white dwarfs with circumstellar dust are accreting planetary material, and (3) the properties of ZZ Ceti stars. The common thread is observations to be obtained using the SOAR telescope with the Goodman Spectrograph, which was built by the PI. With partial support from this award, the PI will build a red-channel for the spectrograph, which is of great interest to the observational community and which will further enable the three key observational programs.