RUI: Theoretical Studies of Astrophysical Jets Using 1-D and2-D analytic Models

摘要 AST-9318745 KOUPELIS，Theodoros 将开发星系外流（喷流）的二维分析模型。 它将被用于部分的方法，首先找到的磁流体动力学（MHD）方程描述的流动的运动积分。 将完成一个一维分析模型的发展，其中理想的MHD方程系统被投影到喷流轴上（窄喷流模型）。 利用这些模型，将对不同的物理机制对各种天体外流的准直和连续加速的相对重要性进行调查。 该项目的第一个目标是找到射流原点物理参数值的允许范围（例如， 磁场强度、密度等）为了使外流成为可能，并研究它的演变，因为接近它的来源的物理条件不断变化。 目标是通过使用沿着其长度的流出观测所提供的信息来研究射流起源处区域的物理学。 第二个目标是检查不同的压力分布和磁场强度的影响，在周围的介质中流出的准直和演变。 目标是研究在不同环境中流出的传播和稳定性。 使用适当的值的参数的利益，或在可用的情况下，所施加的限制，由特定的流出和环境的观察，理论结果将与数值模拟进行比较，并从活跃的核，中子星和prostar的流出。 ***

ABSTRACT AST-9318745 KOUPELIS, Theodoros A two-dimensional analytic model for outflows (jets) in galaxies will be developed. It will be used in part on the approach of first finding the integrals of motion of the magnetohydrodynamic (MHD) equations describing the flow. The development of a one-dimensional analytic model in which the system of the ideal MHD equations is projected onto the jet axis (the narrow-jet model) will be completed. Using these models an investigation of the relative importance of different physical mechanisms on the collimation and continuous acceleration of outflows from a variety of astrophysical objects will be conducted. The first objective of this project is to find the allowed ranges of values of the physical parameters at the jet origin (e.g., magnetic field strength, density, etc.) for an outflow to be possible, and to study its evolution as the physical conditions close to its source change continuously. The goal is to study the physics of the regions at the origin of jets by using the information provided by observations of the outflow along its length. The second objective is to examine the effects of different pressure distributions and magnetic field strengths in the medium surrounding the outflow on its collimation and evolution. The goal is to study the propagation and stability properties of outflows in different environments. Using appropriate values for the parameters of interest or, when available, the limits imposed by the observations of specific outflows and the environments, the theoretical results will be compared with numerical simulations, and with outflows from active nuclei, neutron stars, and prostars. ***