Using APOGEE Chemical Abundances to Probe Formation Scenarios of the Milky Way Bulge

利用 APOGEE 化学丰度探测银河系核核的形成情景

• 批准号: 1801940
• 负责人: Sten Hasselquist
• 金额: $ 10万
• 依托单位: Hasselquist Sten
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2021-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1801940&HistoricalAwards=false
• 关键词: Using; APOGEE; Chemical; Abundances; Probe

Sten Hasselquist is awarded an NSF Astronomy and Astrophysics Fellowship to conduct a program of research and education at the University of Utah. Using high quality spectra of thousands of stars observed with the Apache Point Observatory Galactic Evolution Experiment (APOGEE), Hasselquist will perform a detailed chemical analysis of the Milky Way's central bulge. Because a central bulge seems to be a feature of most disk galaxies, understanding how the bulge of our galaxy formed and evolved will allow astronomers to understand how galaxy formation and evolution occurs across the Universe. Alongside this research, Hasselquist will develop and run an inquiry-based high-altitude balloon program targeted at high school students from groups that are underrepresented in science. Hasselquist will analyze how the mean chemical abundance tracks for each element provided by APOGEE compare between the Milky Way's bulge and inner disk. He will explore chemical abundance correlations in N-dimensional space, analyzing how these correlations differ between bulge and inner disk. From these analyses, conclusions can be drawn about formation mechanisms of the bulge. He will also identify the origin of metal-poor stars in the bulge by invoking clustering algorithms to quantify chemical abundance similarities between the metal-poor bulge and the Milky Way's halo or satellite populations. Additionally, he will use carbon-to-nitrogen abundance ratios to assign a chemical clock to the Galaxy's stars, allowing for an in-depth study of the chemical abundance patterns of the Galaxy's bulge with an added time dimension that is not typically available in large-scale chemical evolution studies. Working with outreach facilities at his host institution, Hasselquist will create a program in which high school students gain valuable critical thinking skills by designing and executing high-altitude balloon experiments to answer specific scientific questions.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.

Sten Hasselquist被授予NSF天文学和天体物理学奖学金，在犹他州大学进行研究和教育计划。 利用阿帕奇点天文台银河演化实验（APOGEE）观测到的数千颗恒星的高质量光谱，哈塞尔奎斯特将对银河系中央隆起进行详细的化学分析。 由于中央隆起似乎是大多数盘状星系的特征，因此了解我们星系的隆起如何形成和演化将使天文学家能够了解整个宇宙中星系的形成和演化。 除了这项研究，哈塞尔奎斯特将开发和运行一个基于调查的高空气球计划，目标是高中学生群体在科学方面代表性不足。 Hasselquist将分析APOGEE提供的每种元素的平均化学丰度轨迹如何在银河系的凸起和内部磁盘之间进行比较。 他将探索N维空间中的化学丰度相关性，分析这些相关性在凸起和内部磁盘之间的差异。 通过这些分析，可以得出有关鼓包形成机制的结论。 他还将通过调用聚类算法来量化贫金属凸起与银河系晕或卫星群之间的化学丰度相似性，从而确定凸起中贫金属恒星的起源。此外，他还将使用碳-氮丰度比为银河系的恒星分配一个化学时钟，以便深入研究银河系凸起的化学丰度模式，并增加一个在大规模化学演化研究中通常不可用的时间维度。 哈塞尔奎斯特将与他所在机构的外展设施合作，创建一个项目，让高中生通过设计和执行高空气球实验来回答特定的科学问题，从而获得宝贵的批判性思维技能。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

The chemical properties of the Milky Way’s on-bar and off-bar regions: evidence for inhomogeneous star formation history in the bulge

• DOI: 10.1093/mnras/staa3256
• 发表时间: 2020-08
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: J. Lian;G. Zasowski;S. Hasselquist;J. Neumann;S. Majewski;R. Cohen;J. Fernández-Trincado;R. Lane;P. Longa-Peña;A. Roman-Lopes

Open Cluster Chemical Homogeneity throughout the Milky Way

• DOI: 10.3847/1538-4357/abb93e
• 发表时间: 2020-09
• 期刊: The Astrophysical Journal
• 作者: Vijith Jacob Poovelil;G. Zasowski;S. Hasselquist;Anil C. Seth;J. Donor;R. Beaton;Katia Cunha

Exploring the Galactic Warp through Asymmetries in the Kinematics of the Galactic Disk

• DOI: 10.3847/1538-4357/abc3c2
• 发表时间: 2020-10
• 期刊: The Astrophysical Journal
• 作者: Xinlun Cheng;B. Anguiano;S. Majewski;C. Hayes;P. Arras;C. Chiappini;S. Hasselquist;Anna Bárbara de Andrade Qu

Identifying Sagittarius Stream Stars by Their APOGEE Chemical Abundance Signatures

• DOI: 10.3847/1538-4357/aafdac
• 发表时间: 2019-01
• 期刊: The Astrophysical Journal
• 作者: S. Hasselquist;J. Carlin;J. Holtzman;M. Shetrone;C. Hayes;K. Cunha;V. Smith;R. Beaton;J. Sobeck

The Open Cluster Chemical Abundances and Mapping Survey. IV. Abundances for 128 Open Clusters Using SDSS/APOGEE DR16

• DOI: 10.3847/1538-3881/ab77bc
• 发表时间: 2020-02
• 期刊: The Astronomical Journal
• 作者: J. Donor;P. Frinchaboy;K. Cunha;J. O’Connell;C. Prieto;Andr'es Almeida;F. Anders;R. Beaton