The Diffuse Interstellar Medium: Magnetic Fields, Physical Parameters and Morphology

弥漫星际介质：磁场、物理参数和形态

• 批准号: 0406987
• 负责人: Carl Heiles
• 金额: --
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-06-15 至 2008-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0406987&HistoricalAwards=false
• 关键词: Diffuse; Interstellar; Medium; Magnetic; Fields

AST 0406987HeilesThis project directed by Dr. Carl Heiles concentrates on measuring physical parameters of the diffuse interstellar medium, which is the matrix within which molecular clouds reside and the medium that soaks up the energy from massive stars as they rapidly evolve to their deaths. Accordingly, it is the medium through which the feedback processes linking stellar birth and death must operate. His interest is clarifying these processes by determining the physical aspects of the diffuse atomic hydrogen (HI) using the radioastronomical techniques with which he is expert. These techniques provide unique information on magnetic field strength, temperature, kinematics, and morphology. He will cover a wide range of size scales, from small dense molecular clouds to the global galactic scale. These studies, together with their comparison with the relevant theories, are crucial for understanding the thermodynamics, magnetogasdynamics, and dynamo processes of the interstellar gas. The present time is particularly appropriate for these studies because the Green Bank Telescope (GBT) has become operational and Arecibo, with its filled aperture and high angular resolution, provides excellent maps. At Arecibo, the mapping will be greatly enhanced by the multifeed array, called ALFA, which should come on line midway through the period covered by this award.In the past Dr. Heiles has worked closely and intensively with the national radio observatories, NRAO and NAIC, performing calibrations in the realms of fundamental beam properties and polarization. Without these efforts, these observatories would not have polarization capability. This tradition will continue. At the GBT the spectral correlator will become usable for polarization work, and Dr. Heiles will calibrate it and develop software for its use. At Arecibo, he will continue his deep involvement with technical details of calibrating the multifeed array system. Also, he will continue our cross-fertilization of undergraduate education andresearch.

这项由卡尔·海尔斯博士指导的项目专注于测量弥漫星际介质的物理参数，漫射星际介质是分子云驻留的矩阵，也是在大质量恒星快速演化直至死亡时吸收能量的介质。因此，它是连接恒星诞生和死亡的反馈过程必须通过的媒介。他感兴趣的是通过使用他擅长的射电天文技术来确定扩散原子氢(HI)的物理方面，从而澄清这些过程。这些技术提供了关于磁场强度、温度、运动学和形态的独特信息。他将涵盖范围广泛的大小尺度，从小而密的分子云到全球银河系尺度。这些研究，以及它们与相关理论的比较，对于理解星际气体的热力学、磁气动力学和发电机过程至关重要。目前的时间特别适合于这些研究，因为绿岸望远镜(GBT)已经投入使用，而阿雷西博的充满光圈和高角度分辨率提供了极好的地图。在阿雷西博，名为阿尔法(Alfa)的多馈源阵列将极大地加强地图绘制，该阵列应该会在本奖项所涵盖的时期中途上线。过去，海尔斯博士与国家射电天文台、NRAO和NAIC密切合作，在基本波束特性和偏振领域进行校准。如果没有这些努力，这些天文台就不会有偏振能力。这一传统将继续下去。在GBT，光谱相关器将可用于偏振工作，海尔斯博士将对其进行校准，并为其使用开发软件。在阿雷西博，他将继续深入参与校准多馈入阵列系统的技术细节。此外，他还将继续我们本科生教育和研究的交叉培养。