Up close and personal: galaxy evolution at high resolution in the Milky Way

自从星系形成研究开始以来，银河系一直是宇宙中了解星系演化物理的最佳地点之一。尤其是今天，当新的天基和陆基调查提供了10亿颗恒星的位置、速度和基本恒星参数，以及数百万颗恒星的详细化学丰度和年龄时，情况尤其如此。这些新的大型数据集为了解银河系详细的进化史提供了巨大的机会，但分析数据并从中推断星系进化的重要元素也带来了一系列新的挑战。这项提议中的工作将通过对天体测量的GAIA数据和光谱SDSS数据的分析和建模，在我们对像银河系这样的盘状星系的演化的理解上取得下一次飞跃。这项建议将重点放在以下几个方面。首先，利用机器学习的新一代光度和光谱数据分析：我们将开发新的机器学习方法，特别是人工智能方法，以确定数百万高分辨率恒星光谱的SDSS-V数据集、数百万恒星的光曲线TESS数据集和GAIA的十亿恒星分光光度数据集的精确恒星参数、丰度、距离和年龄。这将提供大量高质量的数据样本。其次，我们将使用这个新的数据集来研究目前稀疏采样的银河系中央条形/凸起区域的详细结构、动力学和演化。最后，我们将利用新的数据和模拟来研究银河系圆盘在太阳附近和朝向圆盘外边缘的垂直结构，以了解我们和其他团队最近发现的垂直结构中的扰动的起源，以及这些扰动如何影响银河系最近的演化。这些研究的结合将为银河系从最早的起源到现在的演化提供新的见解。

Ever since the dawn of galaxy-formation studies, the Milky Way has been one of the best places in the Universe to learn about the physics of galaxy evolution. This is especially true today, when new space- and ground-based surveys are providing positions, velocities, and basic stellar parameters for a billion stars and detailed chemical abundances and ages for millions of stars. These new large data sets represent an enormous opportunity to learn about the detailed evolutionary history of the Milky Way, but analyzing the data and deducing the important elements of galaxy evolution from this presents a novel set of challenges as well. The work in this proposal will make the next leap in our understanding of the evolution of disk galaxies like the Milky Way, by analysis and modeling of the astrometric Gaia data and spectroscopic SDSS data. This proposal will focus on the following areas. Firstly, next-generation photometric and spectroscopic data analysis using machine learning: we will develop new machine-learning and in particular artificial-intelligence methods to determine precise stellar parameters, abundances, distances, and ages for the SDSS-V data set of millions of high-resolution stellar spectra, the TESS data set of lightcurves of millions of stars, and the billion-star spectrophotometric data set from Gaia. This will provide a large, high-quality data sample. Secondly, we will use this new data set to study the detailed structure, dynamics, and evolution of the currently-sparsely-sampled central bar/bulge region of the Milky Way. Finally, we will investigate the vertical structure of the Milky Way's disk near the Sun and towards the outer edge of the disk with the new data and with simulations to understand the origin of perturbations in the vertical structure that we and other groups have recently found and how these perturbations affect the recent evolution of the Milky Way. The combination of these investigations will provide new insights into the evolution of the Milky Way, from its earliest beginnings until the present day.