A New View of the Chemical Evolution of Nearby Galaxies with Keck and VLT Integral Field Spectroscopy

利用 Keck 和 VLT 积分场光谱观察邻近星系化学演化的新视角

• 批准号: 1816462
• 负责人: Karin Sandstrom
• 金额: $ 25.29万
• 依托单位: University of California-San Diego
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-10-01 至 2022-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1816462&HistoricalAwards=false
• 关键词: New; View; Chemical; Evolution; Nearby

As stars evolve, they produce and distribute heavy elements (i.e. elements heavier than helium) into the interstellar gas. Over time, the heavy element content builds up in a galaxy, increasing the metallicity of the gas. Metallicity has an important role in governing how galaxies form new stars. Metallicity can also change because of inflow of gas from the galaxy's surroundings and outflows of gas from the galaxy disk caused by intense bursts of star formation. Once it is in a galaxy, gas with varying metallicity is mixed together by turbulence and flows. The local metallicity in a galaxy therefore reflects the competition between all of these factors. These investigators will study the region-to-region variation of metallicity in nearby galaxies to learn about how these important processes shape the heavy element content of galaxies. The PI will also lead a program of professional development and mentoring for incoming transfer students to the physical sciences at UC San Diego with the goal of increasing their participation in undergraduate research. The investigators will make the next critical step forward in measuring ISM metallicities in nearby galaxies using new integral field spectroscopic observations performed with the Keck Cosmic Web Imager (KCWI) and the Very Large Telescope Multi-Unit Spectroscopic Explorer (VLT-MUSE). These instruments will obtain high sensitivity, fully-sampled maps of the 3500-9300 Angstrom optical spectrum allowing detailed metallicity studies using temperature-sensitive auroral emission lines of oxygen, nitrogen and sulfur. Previous studies have been limited in their assessment of metallicity due the faintness of the spectral lines needed for accurate metallicity diagnostics. The investigators will use the KCWI and MUSE observations to study metallicity inhomogeneity as a function of galaxy properties such as morphology, specific star formation rate and presence of a stellar bar and they will compare these observations to predictions from galaxy simulations and theory. To broaden participation in science, the PI will lead a series of workshops for transfer students in the physical sciences at UC San Diego to provide training in research skills and guidance in finding research positions. The PI will also initiate organized data collection to track the career path of transfer students. This dataset will be used to assess the effectiveness of the program and develop further strategies for increasing the fraction of underrepresented minorities who pursue advanced degrees in the physical sciences.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.

随着恒星的演化，它们产生重元素（即比氦重的元素）并将其分配到星际气体中。 随着时间的推移，星系中的重元素含量逐渐增加，增加了气体的金属含量。 金属丰度在控制星系如何形成新恒星方面起着重要作用。金属丰度也会因为星系周围气体的流入和星星形成的强烈爆发引起的星系盘气体的流出而改变。一旦进入星系，不同金属含量的气体就会通过湍流和流动混合在一起。 因此，星系中的局部金属丰度反映了所有这些因素之间的竞争。 这些研究人员将研究附近星系中金属丰度的区域间变化，以了解这些重要过程如何塑造星系的重元素含量。 PI还将领导一个专业发展和指导计划，为进入加州大学圣地亚哥分校物理科学的转学生提供指导，目的是增加他们对本科研究的参与。 研究人员将在测量附近星系的ISM金属丰度方面迈出关键的一步，使用Keck Cosmic Web Imager（KCWI）和超大望远镜多单元光谱探测器（VLT-MUSE）进行新的积分场光谱观测。这些仪器将获得3500-9300埃光谱的高灵敏度全采样图，从而能够利用对温度敏感的氧、氮和硫极光发射线进行详细的金属丰度研究。由于准确的金属丰度诊断所需的光谱线模糊，以前的研究在金属丰度评估方面受到限制。研究人员将使用KCWI和MUSE观测来研究金属丰度不均匀性作为星系特性的函数，如形态，特定的星星形成速率和恒星棒的存在，他们将这些观测结果与星系模拟和理论的预测进行比较。为了扩大对科学的参与，PI将为UC San Diego的物理科学转学生举办一系列研讨会，以提供研究技能培训和寻找研究职位的指导。PI还将启动有组织的数据收集，以跟踪转学生的职业道路。该数据集将用于评估该计划的有效性，并制定进一步的战略，以增加在物理科学领域攻读高级学位的少数民族的比例。该奖项反映了NSF的法定使命，并被认为值得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来支持。

项目成果

The DUVET Survey: Direct T e -based Metallicity Mapping of Metal-enriched Outflows and Metal-poor Inflows in Markarian 1486

DUVET 调查：马卡里安 1486 年富金属流出量和贫金属流入量的直接基于 T 的金属丰度测绘

• DOI: 10.3847/2041-8213/ac18ca
• 发表时间: 2021
• 期刊: The Astrophysical Journal Letters
• 作者: Cameron, Alex J.;Fisher, Deanne B.;McPherson, Daniel;Kacprzak, Glenn G.;Berg, Danielle A.;Bolatto, Alberto;Chisholm, John;Herrera-Camus, Rodrigo;Nielsen, Nikole M.;Reichardt Chu, Bronwyn
• 通讯作者: Reichardt Chu, Bronwyn

Keck Cosmic Web Imager Observations of He ii Emission in I Zw 18

凯克宇宙网络成像仪对 I Zw 18 中 He ii 发射的观测

• DOI: 10.3847/2041-8213/abf09b
• 发表时间: 2021
• 期刊: The Astrophysical Journal Letters
• 作者: Rickards Vaught, Ryan J.;Sandstrom, Karin M.;Hunt, Leslie K.
• 通讯作者: Hunt, Leslie K.

DUVET: Spatially Resolved Observations of Star Formation Regulation via Galactic Outflows in a Starbursting Disk Galaxy

DUVET：通过星爆盘星系中的星系流出对恒星形成调节进行空间分辨观测

• DOI: 10.3847/1538-4357/aca1bd
• 发表时间: 2022
• 期刊: The Astrophysical Journal
• 作者: Reichardt Chu, Bronwyn;Fisher, Deanne B.;Bolatto, Alberto D.;Chisholm, John;Fielding, Drummond;Berg, Danielle;Cameron, Alex J.;Glazebrook, Karl;Herrera-Camus, Rodrigo;Kacprzak, Glenn G.
• 通讯作者: Kacprzak, Glenn G.

The 2D metallicity distribution and mixing scales of nearby galaxies

邻近星系的二维金属丰度分布和混合尺度

• DOI: 10.1093/mnras/stab3082
• 发表时间: 2021
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: Williams, Thomas G;Kreckel, Kathryn;Belfiore, Francesco;Groves, Brent;Sandstrom, Karin;Santoro, Francesco;Blanc, Guillermo A;Bigiel, Frank;Boquien, Médéric;Chevance, Mélanie
• 通讯作者: Chevance, Mélanie