New Probes of Galactic Outflows at the Peak Epoch of Star Formation

星系的形成受到大规模气体外流形式的反馈的调节。这个过程的细节知之甚少，因为很难观察到气体的微弱发射。首席研究员（PI）琼斯已经确定了一个引力透镜星系的样本，其中一个前景星系弯曲了来自遥远星系的光，并放大了其微弱的发射。PI将使用位于W。M.凯克天文台研究银河系外流如何塑造他们的形成百亿年前。作为该计划的一部分，PI将在加州州立数学与科学暑期学校（COSMOS）向高中生教授科学研究方法，包括星系和宇宙学讲座，以及使用加州大学戴维斯分校屋顶望远镜设施介绍观测天文学技术。这一提议将支持对现有数据的分析和对更大样本的进一步观察。积分场光谱与KCWI仪器将映射的空间范围和运动学的流出气体使用荧光发射线，这将提高估计的质量损失率。同样的数据也可以绘制出吸收过程中流出气体的地图，这可以探测流出气体的能量学和发射地点以及化学成分。非难熔元素硫提供了相对于中性氢的总阿尔法元素金属量的测量，而其他元素如硅和镍对尘埃含量和丰度模式敏感。总的来说，这些结果将解决星系外流的物理特性及其在调节星系组装红移z=2- 3的作用。该奖项反映了NSF的法定使命，并已被认为是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的支持。

Galaxy formation is regulated by feedback in the form of large-scale outflows of gas. The details of this process are poorly understood as it is difficult to observe the faint emission from the gas. Principal Investigator (PI) Jones has identified a sample of gravitationally lensed galaxies, where a foreground galaxy bends the light from the distant galaxy and magnifies its weak emission. The PI will observe these lensed galaxies using the Keck Cosmic Web Imager (KCWI) instrument at the W. M. Keck Observatory to study how galactic outflows shaped their formation ten billion years ago. As part of this program the PI will teach scientific research methods to high school students in the California State Summer School for Mathematics and Science (COSMOS), with lectures on galaxies and cosmology, and an introduction to observational astronomy techniques using a rooftop telescope facility at the University of California - Davis campus. This proposal will support the analysis of data already in hand and additional observations of a larger sample. Integral field spectroscopy with the KCWI instrument will map the spatial extent and kinematics of outflowing gas using fluorescent emission lines, which will improve estimates of the mass loss rates. The same data also enable maps of the outflowing gas in absorption, which probes outflow energetics and launching sites as well as the chemical composition. The non-refractory element sulfur provides a measurement of total alpha-element metallicity relative to neutral hydrogen, while other elements such as silicon and nickel are sensitive to dust content and abundance patterns. Collectively these results will address the physical properties of galactic outflows and their role in regulating galaxy assembly at redshifts z=2-3.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.