Collaborative Research: Chemical Cartography in the Milky Way with APOGEE

合作研究：与 APOGEE 进行银河系化学制图

• 批准号: 1109718
• 负责人: Steven Majewski
• 金额: $ 25.22万
• 依托单位: University of Virginia Main Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-08-01 至 2014-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1109718&HistoricalAwards=false
• 关键词: Collaborative; Research; Chemical; Cartography; Milky

The PI and his team work on the scientific outcomes from the large and systematic survey for precision stellar elemental abundance analyses that is set out to map the spatial variations in the chemistry across the Milky Way Galactic disk. They employ the Apache Point Observatory Galactic Evolution Experiment (APOGEE) in the Sloan Digital Sky Survey (SDSS)-III survey, which is a large-scale, near-infrared (H-band), high-resolution (R ~ 30,000), high signal-to-noise (100) spectroscopic survey of Milky Way stellar populations. The survey covers wavelengths from 1.51-1.68 microns which is a region that includes useful absorption lines from about 15 chemical elements, including alpha, odd-numbered, and iron peak elements. A three-year bright-time observing campaign from 2011-2014 will enable APOGEE to observe about 100,000 giants stars across the Galactic bulge, disk and halo, with the vast majority of these stars in the disk. This large catalog of chemical abundance data for stars all across the Milky Way from APOGEE is used to address a number of key questions related to the chemistry of the Galactic disk.The analysis of the data from the APOGEE pipeline gives the stellar parameters (e.g., effective temperatures, gravity, metallicity) and abundances for about 15 elements which are used to deduce additional stellar properties (star-by-star extinctions, distances, ages) that are needed to map the abundances in the disk and to constrain models of Galactic chemical evolution. These maps provide the three-dimensional distributions represent an order of magnitude improvement in what has been achieved before in terms of numbers of stars included, numbers of chemical elements probed, homogeneity in the collection, reduction, and calibration of the data, and spatial coverage, including vast regions of the disk never before probed because of the limitations from dust. As part of this work, the team plans to release a value-added APOGEE catalog of extinctions, distances and age estimates, along with the APOGEE data on abundances of about 15 chemical elements for about 100,000 stars from the thin and thick disks, and the reduction of these data into multidimensional maps of elemental abundances. These data should have significant value to the wider community of Galactic chemical evolution modelers.

首席研究员和他的团队致力于对精确恒星元素丰度分析进行大规模系统调查的科学成果，旨在绘制整个银河系盘中化学物质的空间变化图。他们在斯隆数字巡天 (SDSS)-III 巡天中采用了阿帕奇点天文台银河演化实验 (APOGEE)，这是一项大规模、近红外（H 波段）、高分辨率（R ~ 30,000）、对银河系恒星群的高信噪比 (100) 光谱调查。该调查涵盖 1.51-1.68 微米的波长，该区域包含约 15 种化学元素的有用吸收线，其中包括 α、奇数和铁峰元素。 2011-2014年为期三年的明亮时间观测活动将使APOGEE能够观测到横跨银河核球、盘和晕的约10万颗巨星，其中绝大多数恒星位于盘中。来自 APOGEE 的整个银河系恒星的化学丰度数据大目录用于解决与银盘化学相关的许多关键问题。对 APOGEE 管道数据的分析给出了恒星参数（例如，有效温度、重力、金属丰度）和大约 15 种元素的丰度，用于推断绘制盘中丰度图和银河系化学演化的约束模型。这些地图提供的三维分布代表了之前在所包含的恒星数量、探测的化学元素数量、数据收集、减少和校准的均匀性以及空间覆盖方面所取得的数量级的改进，包括由于灰尘的限制而以前从未探测过的磁盘的大片区域。作为这项工作的一部分，该团队计划发布一个包含灭绝、距离和年龄估计的增值 APOGEE 目录，以及来自薄盘和厚盘的约 100,000 颗恒星的约 15 种化学元素丰度的 APOGEE 数据，以及将这些数据简化为元素丰度的多维图。这些数据对于更广泛的银河化学演化建模者群体应该具有重要价值。