Collaborative Research: Addressing the Burning Questions in the Baryon Cycle at z~2

天文学家想要了解星系是如何生长的。他们特别想知道为什么宇宙还很年轻时恒星形成的速度最快。Shapley、Reddy和Steidel将分析用凯克望远镜获得的数千个遥远星系的观测结果。他们将研究流入和流出星系的物质如何影响恒星形成的速度和其他关键的星系性质。与全球望远镜大使计划合作，国际和平研究所将开发跨越夜空的互动旅游。其中一次旅行将演示望远镜如何充当时光机。当地高中生和他们的老师将被邀请参加加州理工大学的暑期研究连接项目。PI和她的团队将把学生培养成未来的科学家。Shapley，Reddy和Steidel在Keck重子结构调查(KBSS)和MOSFIRE深部演化场(MOSDEF)调查中发现了宇宙恒星形成高峰期(z~1.5-3.5)的一个具有代表性的星系样本。大约20%的星系也有很深的Keck/LRIS REST-UV光谱，大约100个星系有来自Keck KCWI仪器的积分场单位图。联合PIS将在这一时期建立星系内气体和恒星的稳健的金属丰度测量；它们将根据“下桶”星系光谱学确定气体流出和流入的运动学和几何学；它们将绘制更广泛的环星系介质(CGM)中的气体分布和运动学图，将CGM尺度的特性与星系尺度上的特性联系起来。总而言之，这些结果将检验和提供星系演化中重子循环的前沿模型。由简化的Keck MOSFIRE、LRIS和KCWI光谱数据组成的遗留数据集将在公共档案中提供。该奖项反映了NSF的法定使命，并已通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Astronomers want to understand how galaxies grow. In particular they want to know why the rate of star formation was highest when the Universe was young. Shapley, Reddy, and Steidel will analyze observations of thousands of distant galaxies obtained with the Keck Telescopes. They will investigate how material flowing into and out of a galaxy can affect the rate of star formation and other key galaxy properties. In partnership with the WorldWide Telescope Ambassadors Program the PIs will develop interactive tours across the night sky. One tour will demonstrate how telescopes act as time machines. Local high school students and their teachers will be invited to participate in a Summer Research Connection program at Caltech. The PI and her team will train the students to be future scientists.Shapley, Reddy, and Steidel have identified a representative sample of galaxies at the epoch of peak star formation in the universe (z~1.5-3.5) in the Keck Baryonic Structure Survey (KBSS) and the MOSFIRE Deep Evolution Field (MOSDEF) Survey. A subset of ~20% also have deep Keck/LRIS rest-UV spectra, and ~100 galaxies have integral- field unit maps from the Keck KCWI instrument. The co-PIs will establish robust metallicity measurements of gas and stars within galaxies at this epoch; they will determine the kinematics and geometry of gas outflow and inflow based on "down the barrel" galaxy spectroscopy; they will map the gas distribution and kinematics in the more extended circumgalactic medium (CGM), connecting the CGM-scale properties with those on the galaxy scale. Collectively, these results will test and inform forefront models of baryonic cycling in galaxy evolution. A legacy dataset consisting of the reduced Keck MOSFIRE, LRIS, and KCWI spectroscopic data will be available in a public archive.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.