Collaborative Research: Exploring Star Formation in the Early Universe through Investigations of High-Redshift ISM

合作研究：通过研究高红移 ISM 探索早期宇宙中的恒星形成

• 批准号: 0709235
• 负责人: Jason Prochaska
• 金额: $ 25.55万
• 依托单位: University of California-Santa Cruz
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-08-01 至 2012-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0709235&HistoricalAwards=false
• 关键词: Collaborative; Research; Exploring; Star; Formation

AST-0708543/0709235Wolfe/ProchaskaThis collaboration, led by Dr. A.Wolfe, will examine the relationship between neutral gas and young stars at high redshift, by applying diagnostic tools developed for the local interstellar medium (ISM). Most of what we know about star formation in high-redshift galaxies stems from observing them in emission, but damped Lyman-alpha systems (DLAs) are detected in absorption against quasars. In general, these galaxies are more representative than any other high-redshift objects detected in emission. This study will (1) discover and analyze over 1000 new DLAs, identifying a large sample of galaxies for ISM research, (2) triple the number of DLAs with detected carbon-II absorption in the ultraviolet, to measure the gas cooling and heating rates, (3) pursue preliminary observations of carbon-II emission in the sub-millimeter wavelength range, coming from the cold neutral gas in DLAs, to determine the sizes and masses of high-redshift galaxies, (4) search for Hydrogen-alpha emission from DLAs, mapping the velocity field of the ionized gas for evidence of galaxy rotation, (5) measure the temperature, density, molecular content and multi-phase structure of the ISM in young galaxies, and finally, (6) measure magnetic fields in intermediate-redshift DLAs by detecting Zeeman splitting in the 21-cm absorption lines using the Green Bank Telescope.The impact of DLA science has steadily grown beyond the field of quasar absorption lines, to include chemical evolution and nucleosynthesis in the early Universe, variations in the fine-structure constant; and global constraints on critical aspects of galaxy formation. The present research will therefore be widely disseminated to the astronomical population, and beyond to the general education community through an advanced Web site. In addition, support for graduate students and exposing undergraduates to cutting-edge research are staple activities of these researchers.

由A.Wolfe博士领导的AST-0708543/0709235Wolfe/Prochaskathis合作将通过应用为当地的星际媒体开发的诊断工具（ISM），研究中性气和高红移的中性气与年轻恒星之间的关系。 我们对高红移星系中恒星形成的大部分内容源于在发射中观察它们，但是在吸收对类星体的吸收中，检测到阻尼的Lyman-Alpha系统（DLAS）。 通常，这些星系比发射中检测到的任何其他高红移对象更具代表性。 这项研究将（1）发现和分析超过1000种新的DLA，确定大量用于ISM研究的星系样本，（2）在紫外线中检测到的碳-II吸收的DLA数量的数量三倍，以测量气体冷却和加热速率，（3）在碳-II中的碳 - II在碳-II II中的初步观察，从而确定碳-II量的中性范围。 the sizes and masses of high-redshift galaxies, (4) search for Hydrogen-alpha emission from DLAs, mapping the velocity field of the ionized gas for evidence of galaxy rotation, (5) measure the temperature, density, molecular content and multi-phase structure of the ISM in young galaxies, and finally, (6) measure magnetic fields in intermediate-redshift DLAs by detecting Zeeman splitting in使用绿色银行望远镜的21厘米吸收线。DLA科学的影响稳步增长，超出了类星体吸收线领域，包括早期宇宙中的化学演化和核合成，在细构造常数中的变化；以及全球对星系形成关键方面的限制。 因此，本研究将通过先进的网站广泛地传播到天文学人群，及其他通识教育社区。 此外，这些研究人员的主食是对研究生的支持和对尖端研究的本科生的支持。