Radio Polarization and Spectra of Variable Extragalactic Objects

经常测量总磁通密度和线性 河外射电源的极化将在 频率为4.8、8.0和14.5 GHz，使用Michigan 26米 射电望远镜 将开发和拟合理论模型 这些数据来研究发射过程中的物理条件 区域，并研究粒子能量产生机制。 这些观察结果将由甚长基线补充 与其他机构合作进行的干涉测量（VLBI）观测 研究人员 还将在0.85、1.4和2.7下进行观察 GHz与国家射电天文台91米 望远镜，以研究低- 频率可变源 研究的具体目标 包括：a）获得高时间分辨率、多频率 孤立爆发的极化和通量密度数据， 为了测试详细的理论模型， 区域，B）开发更复杂的冲击模型 在相对论性射流中传播， 发射区域的物理参数，c）更好地 理解内在和外在的相对重要性 和机制作为分米制变化的原因， “中频差距”的性质，d）改善全球 活动星系核的模型，通过同时，广泛的， 波段（通过无线电波长的紫外线或X射线） 观察，以及e）获得以下的形态学信息 选定的来源，以测试模型的发射区。

Frequent measurements of the total flux density and linear polarization of extragalactic radio sources will be made at a frequency of 4.8, 8.0 and 14.5 GHz using the Michigan 26 meter radio telescope. Theoretical models will be developed and fitted to these data to study the physical conditions in the emitting regions and to study the particle energy generation mechanisms. These observations will be supplemented by Very Long Baseline Interferometry (VLBI) observations in collaboration with other researchers. Observations will also be made at 0.85, 1.4 and 2.7 GHz with the National Radio Astronomy Observatory 91 meter telescope to investigate the broad-band characteristics of low- frequency variable sources. Specific objectives of the research include: a) to obtain high time-resolution, multifrequency polarization and flux density data of isolated outbursts in order to test detailed theoretical models of the source emitting region, b) to develop more sophisticated models of shocks propagating in relativistic jet flows which constrain more of the physical parameters of the emitting regions, c) to better understand the relative importance of intrinsic and extrinsic and mechanisms as causes of decimetric variability, and the nature of the "intermediate frequency gap" , d) to improve global models of active galactic nuclei through simultaneous, broad- band (Ultraviolet or X-ray through radio wavelengths) observations, and e) to obtain morphological information of selected sources to test models of the emitting regions.