Polarization Structure and Evolution of Compact Extragalactic Radio Jets

AST-9900723致密河外射电喷流的偏振结构和演化。阿勒正在利用密歇根大学26米抛物面进行每周一次的单碟线偏振和通量密度测量，以及每两个月一次的VLBI/P偏振测量观测。 有19个来源。 过去的观测表明，通量和偏振的变化是河外天体的一个普遍和潜在的特征。此外，阿勒博士正在开发新的辐射传输模型，将斜激波的发展纳入相对论流。 该计划的目标是了解高度准直的相对论性喷流的结构和演化，具体目标是确定斜激波是否可以解释在偏振结构的时间变化观测中发现的行为范围，或者是否必须调用额外的机制剪切来解释长期稳定性。

AST-9900723Polarization structure and evolution of compact extragalactic radio jetsHugh D AllerDr. Aller is conducting weekly single dish linear polarization and flux density measurements with the 26 meter University of Michigan paraboloid, and bi-monthly VLBI/P polarimetry observations. Nineteen sources are followed. Past observations have shown that flux and polarization variability is an all pervasive and underlying feature of extragalactic objects.In addition Dr. Aller is developing new radiative transfer models incorporating the development of oblique shocks in the relativistic flow. The goal of the program is to learn about the structure and evolution of highly collimated, relativistic jets with the specific goal of determining whether oblique shocks can account for the range of behavior found in observations of the temporal variations in polarization structure or whether an additional mechanism, shear, must be invoked to explain the long term stability.***