Empirical Calibration of Feedback Processes in Galaxy Evolution

星系演化中反馈过程的经验校准

• 批准号: 0808161
• 负责人: Crystal Martin
• 金额: $ 38.25万
• 依托单位: University of California-Santa Barbara
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-06-01 至 2012-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0808161&HistoricalAwards=false
• 关键词: Empirical; Calibration; Feedback; Processes; Galaxy

When a galaxy undergoes vigorous starbirth, supernova explosions and the winds of massive stars heat the surrounding gas, and can drive it from the galaxy as a wind. Since stars form only from cool dense gas, this 'feedback' regulates the pace of starbirth. The Principal Investigator will study gas outflows from star-forming galaxies, both locally and at distances so large that we see the galaxies as they were when the cosmos was only half its present age. In the nearby galaxies, spectral lines of many atoms and ions will be studied across the face of the galaxy, to trace gas at different stages of ionization and at different depths within the wind. Radiative transfer computations will be used to interpret the observations, to search for regions of shocked gas and to estimate how much mass is leaving the galaxy. These detailed studies will be used to interpret observations of the more distant galaxies where fewer spectral lines can be studied. The results will help us to understand how galaxies form, and what controls the rate at which they make their stars. Two graduate students, a woman and a Latino man, will be trained by participating in the research. The Principal Investigator accompanies the 'UC Santa Barbara Physics Circus' annually on a visit to a local elementary school. She also works with UCSB colleagues to present a popular public lecture series at the Santa Barbara Museum of Natural History; the lectures are recorded and aired on local television. These outreach activities will be supported and enhanced by her research. The Principal Investigator will also contribute to research infrastructure by helping to build the science case for instruments for the planned Thirty Meter Telescope.

当一个星系经历剧烈的恒星诞生时，超新星爆炸和大质量恒星的风会加热周围的气体，并可以将其以风的形式驱赶出星系。 由于恒星只能由冷而稠密的气体形成，这种“反馈”调节了恒星诞生的速度。 首席研究员将研究恒星形成星系的气体流出，无论是在本地还是在远距离处，以至于我们可以看到宇宙年龄只有现在一半时的星系。 在附近的星系中，将研究整个星系表面的许多原子和离子的谱线，以追踪风中不同电离阶段和不同深度的气体。 辐射传输计算将用于解释观测结果，寻找冲击气体区域并估计有多少质量离开星系。 这些详细的研究将用于解释对更遥远星系的观测结果，在这些星系中可以研究的谱线较少。 这些结果将帮助我们了解星系是如何形成的，以及是什么控制着它们形成恒星的速度。 两名研究生，一名女性和一名拉丁裔男性，将通过参与这项研究来接受培训。首席研究员每年都会陪同“加州大学圣巴巴拉分校物理马戏团”参观当地的一所小学。 她还与加州大学圣巴巴拉分校的同事合作，在圣巴巴拉自然历史博物馆举办了一系列受欢迎的公开讲座；讲座被录制并在当地电视台播出。这些外展活动将得到她的研究的支持和加强。首席研究员还将通过帮助为计划中的三十米望远镜建立仪器科学案例来为研究基础设施做出贡献。