High Resolution Stellar Spectroscopy

关于银河系的基本问题之一是它的元素组成以及这种组成是如何产生的。据信，形成银河系的原始气体完全由氢和氦组成。从那时起，大多数较重的元素都是在恒星内部和恒星爆炸期间通过核合成形成的。这项研究的目的是提高我们对银河系中化学元素的起源和分布的认识。为此，首席研究员（PI）将专注于四个不同但相关的项目：1。利用银河系晕星的丰度分布曲线，推断银河系第一代大质量恒星及其核合成产物的性质；2. 研究轻元素（如锂、碳、氮、氧）在银河系光晕和盘状巨星对流包层中的混合；3. 利用行星状星云中中性气体的星云吸收和发射谱线，了解前体恒星的核历史；和4。将弥漫性星际波段的高信噪比光谱对准选定的、非常轻微变红的视线，以便获得波段起源的线索。

One of the fundamental questions concerning the Milky Way Galaxy is its elemental composition and how this composition came about. It is believed that the original gas from which our Galaxy formed, consisted of entirely hydrogen and helium. Most of the heavier elements were formed since then by nucleosynthesis in stellar interiors and during stellar explosions. The aim of the research proposed here is to improve our under- standing of the origin and distribution of the chemical elements in our Galaxy. To this end, the Principal Investigator (PI) will focus on four distinct, but related projects: 1. Use abundance distribution curves for the Galaxy's halo stars to deduce the nature of the first generation of massive stars in the Galaxy and their nucleosynethesized products; 2. study the mixing of light elements (e.g., lithium, carbon, nitrogen, oxygen) in the convective envelopes of giant stars in the Galaxy's halo and disk; 3. use nebular absorption and emission lines of neutral gas in planetary nebulae to learn about the nuclear history of the precursor stars; and 4. take very high signal-to-noise spectra of diffuse interstellar bands towards selected, very lightly reddened lines of sight in order to obtain clues as to the bands'origin.