Models of Extragalactic Jets

河外喷流模型

• 批准号: 8717912
• 负责人: Paul Wiita
• 金额: $ 5.7万
• 依托单位: Georgia State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-07-15 至 1990-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8717912&HistoricalAwards=false
• 关键词: Models; Extragalactic; Jets

Models of extragalactic radio jets will be constructed using a variety of numerical approaches. An essentially three-dimensional boundary-following code will be used to continue to investigate the formation and evolution of radio jets. In particular, the bending of jets by ram pressure as the central galactic source moves through an external medium, the growth of non-axisymmetric instabilities, and the effects of a precessing source of jet fluid, will all be studied. Recently developed analytic models of jet propagation from a galactic halo across a pressure-matched interface into an extremely hot intergalactic medium will be developed further. Preliminary calculations using this idea seem to provide good explanations for both the current average size of strong radio sources and the fact the such sources were significantly samller at earlier cosmological epochs. Numerical models of this situation will be developed using both the three-dimensional boundary following code and a full two-dimensional hydrodynamics code and more detailed comparisons with statistical data will be made. Analytic models for jet instabilities will be applied to Very Large Array (VLA) radio maps of a particularly interesting radio source with a single, oscillatory jet feeding into a diffuse lobe. A general model for the continuum electromagnetic emission from active galactic nuclei, based on coherent plasma processes, will be further developed and compared with observations.

河外射电喷流的模型将使用 各种数值方法。 基本 三维边界跟踪代码将用于 继续研究无线电的形成和演变 喷气机。 特别是，由于冲压压力， 中央星系源通过外部介质移动， 非轴对称不稳定性的增长，以及 旋进源射流流体，都将进行研究。 最近发展的射流传播的分析模型， 星系晕穿过压力匹配的界面， 极热的星系际介质将得到进一步发展。 使用这种想法的初步计算似乎提供了良好的 解释了目前强射电的平均大小 来源和事实，这些来源是显着小 在宇宙学早期。 数字模型对此 情况将开发使用两个三维 边界跟踪代码和一个完整的二维流体力学 代码和更详细的比较与统计数据将 进行了 射流不稳定性的分析模型将应用于非常 一个特别有趣的无线电的大阵列（VLA）无线电地图 一个单一的源，振荡射流送入扩散器 耳垂。 连续电磁辐射的一般模型 基于相干等离子体过程的活动星系核， 进一步发展，并与观察结果进行比较。