Supernova Remnants Interacting with Molecular Clouds

超新星遗迹与分子云相互作用

• 批准号: 0307423
• 负责人: Farhad Yusef-Zadeh
• 金额: --
• 依托单位: Northwestern University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-06-01 至 2007-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0307423&HistoricalAwards=false
• 关键词: Supernova; Remnants; Interacting; Molecular; Clouds

AST 0307423Yusef-ZadehA supernova explosion creates an expanding bubble of hot gas which sweeps up the surroundingmedium. Since the massive stars that become supernovae cannot drift far from their parent molecular clouds during their short lifetimes, the interaction of supernova remnants and molecular clouds should be a common occurrence. When a supernova remnant encounters a dense interstellar cloud, the compression may trigger gravitational collapse resulting in the formation of a new generation of stars. There is a great deal of interest in the regions of the interactions, especially where multi-wavelength observations can test theoretical models of shock waves within clouds. The expanding shock wave accelerates particles to high energies and may be responsible for the origin of Galactic cosmic ray particles. The interaction of supernova remnants and molecular clouds can be detected through intense stimulated emission in the 1720 MHz transition of the hydroxyl radical, OH. The maser (a microwave counterpart to laser) emission yields unique insights into the physical processes and conditions occurring during the interaction. Detailed modeling of the production and excitation of these species during the interaction will be used in this project led by Dr. Farhad Yusef-Zadeh to critically evaluate the theory of interstellar shock waves, the origin of supernova remnant masers, and the effect of X-rays emitted by the remnant on ionization and chemistry in the shocked gas. It will also enable the discovery of additional interactions between supernovae and interstellar clouds that will be crucial for future studies. The three-year program, which combines both theory and observations, will provide a crucial window into the physical and chemical processes occurring in shock waves induced within the cloud by the interaction. The scientific aspects of this project will be closely related to education and public outreachcomponents in three areas, each targeting a different audience. The goals of each outreach component are to help the public understand the process of scientific research, to communicate fundamental scientific concepts and to present the specific motivations and research results of this scientific program. Dr. Yusef-Zadeh has been working with programmers and educators to create and distribute learning-based problems to introduce the science topics of this project into undergraduate education at Northwestern and other universities. Dr. Yusef-Zadeh and colleagues have selected eight problems for a course to be offered as "Imaging in Astronomy". One of the problems will be using multi-wavelength observations of the W28 supernova remnant to discuss the physical and spatial relationships between X-ray, maser and synchrotron emitting gas. Building upon the strong relationship with the Adler Planetarium & Astronomy Museum in Chicago, a series of interactive educational products are being deployed to encourage the public understanding of research, as well as to present research results. Dr. Yusef-Zadeh will be working closely with educator and multimedia developers at Northwestern University to provide content and motivations needed for such activities. Dr. Yusef-Zadeh, educators, and undergraduate students at Northwestern are working on the second phase of a website (spaceimages.northwestern.edu). The space imageswebsite provides visitors with astronomy images and image manipulation tools along withnecessary contextual information.***

超新星爆炸会产生一个膨胀的热气泡，它会扫过周围的介质。由于成为超新星的大质量恒星在其短暂的生命周期内无法远离它们的母体分子云，超新星残骸和分子云的相互作用应该是经常发生的。当超新星残骸遇到密集的星际云时，压缩可能会引发引力坍缩，从而形成新一代恒星。人们对相互作用的区域非常感兴趣，特别是在多波长观测可以测试云内激波的理论模型的地方。膨胀的激波将粒子加速到高能量，可能是银河宇宙射线粒子的起源。超新星残余物与分子云的相互作用可以通过氢氧自由基OH在1720 MHz跃迁的强烈受激辐射来探测。微波激射器（激光的微波对应物）发射产生了对相互作用期间发生的物理过程和条件的独特见解。Farhad Yusef-Zadeh博士领导的这个项目将在相互作用期间对这些物质的产生和激发进行详细的建模，以批判性地评估星际激波理论、超新星遗迹脉泽的起源、以及遗迹发出的x射线对激波气体中电离和化学的影响。它还将有助于发现超新星和星际云之间的其他相互作用，这对未来的研究至关重要。这个为期三年的项目结合了理论和观测，将为研究由相互作用引起的云内激波中发生的物理和化学过程提供一个关键的窗口。这个项目的科学方面将与三个领域的教育和公共宣传部分密切相关，每个领域都针对不同的受众。每个外联部分的目标是帮助公众了解科学研究的过程，传达基本的科学概念，并展示这一科学计划的具体动机和研究成果。Yusef-Zadeh博士一直在与程序员和教育工作者合作，创建和分发基于学习的问题，将这个项目的科学主题引入西北大学和其他大学的本科教育。Yusef-Zadeh博士及其同事为一门名为“天文学成像”的课程选择了8个问题。其中一个问题将是利用W28超新星遗迹的多波长观测来讨论x射线、脉泽和同步加速器发射气体之间的物理和空间关系。在与芝加哥阿德勒天文馆和天文博物馆建立牢固关系的基础上，一系列互动教育产品正在部署，以鼓励公众对研究的理解，并展示研究成果。Yusef-Zadeh博士将与西北大学的教育工作者和多媒体开发人员密切合作，为此类活动提供所需的内容和动机。Yusef-Zadeh博士、教育工作者和西北大学的本科生正在为一个网站（spaceimages.northwestern.edu）的第二阶段工作。空间图像网站为访问者提供天文图像和图像处理工具以及必要的上下文信息