US-France Cooperative Research: Magnetic Fields in Star Forming Regions

美法合作研究：恒星形成区域的磁场

• 批准号: 9116356
• 负责人: Thomas Troland
• 金额: $ 1.35万
• 依托单位: University of Kentucky
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-05-15 至 1995-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9116356&HistoricalAwards=false
• 关键词: US; France; Cooperative; Research; Magnetic

This three-year award will support U.S.-France cooperative research in galactic astronomy involving Thomas Troland, University of Kentucky, Richard Crutcher, University of Illinois, and Ilya Kazes at the Observatoire de Meudon in France. The investigators propose to continue their successful research on magnetic field strengths in the evolution of interstellar clouds and star formation. Magnetic fields have emerged as a mechanism for explaining star formation and other cosmic phenomena. The only known technique for measuring magnetic field strength is detection of the Zeeman effect in radio frequency spectral lines. The U.S. and French investigators will continue their survey observations of the OH Zeeman effect of dark clouds using the VLA (Very Large Array), Green Bank and the Arecibo telescopes. They will extend their research to denser regions by observing the Zeeman effect in the 3-mm lines of CN using the IRAM 30-m telescope. This experiment will allow direct probing of magnetic fields at a crucial stage in star formation when core fragmentation and collapse are taking place. Observations with the IRAM telescope is essential since its collecting area is sizeable and will allow for observations in denser regions of space. The project will benefit from French expertise in observation and access to the IRAM facility in Europe. Through the observational program, the investigators will be able to test fundamental theories of magnetic fields in interstellar clouds and enhance our understanding of the role of magnetic fields in star formation.

这个为期三年的奖项将支持美国和法国在银河天文学方面的合作研究，包括Thomas Troland、肯塔基大学、Richard Crutcher、伊利诺伊大学和法国Meudon天文台的Ilya Kazes。研究人员建议继续他们在星际云演化和恒星形成过程中磁场强度的成功研究。磁场已经成为解释恒星形成和其他宇宙现象的一种机制。唯一已知的测量磁场强度的技术是探测无线电频谱线中的塞曼效应。美国和法国的调查人员将继续使用VLA（甚大阵列）、Green Bank和阿雷西博望远镜对黑云的OH塞曼效应进行调查观测。他们将把研究扩展到更密集的区域，使用IRAM 30米望远镜在CN的3毫米线上观察塞曼效应。这个实验将允许在恒星形成的关键阶段，当核心破碎和坍缩发生时，直接探测磁场。IRAM望远镜的观测是必不可少的，因为它的收集区域相当大，可以在更密集的空间区域进行观测。该项目将受益于法国在观测和进入欧洲IRAM设施方面的专业知识。通过观测计划，研究人员将能够测试星际云磁场的基本理论，并增强我们对磁场在恒星形成中的作用的理解。