Radio Monitoring and High-Resolution Imaging of extreme Blazars and other TeV-Detected Active Galaxies with the Effelsberg 100-m Telescope and the Global Millimetre VLBI Array

极端耀变体代表了具有准直相对论等离子体喷流的活动星系的一个亚类，与“常规”耀变体相比，其发射的最大能量范围更高，达到了几个数量级，远达TeV伽马射线范围。虽然目前已知的极端耀变体只有少数，但很明显，它们代表了未来十年高能天文学和天体粒子物理学研究中高度相关的众多天体。在超高能宇宙射线的来源及其相关的极端粒子加速过程，以及高能天体物理中微子的可能来源的背景下，极端耀变体特别令人感兴趣。无线电系统提供了前所未有的高角分辨率成像和高灵敏度光谱通量密度研究的可能性，以探测这种相对论性等离子体射流的结构和动力学过程。极端耀变体的射电辐射相对较弱，尚未得到很好的研究。在这个项目中，我们将使用Effelsberg 100米射电望远镜对tev耀变体进行新的长期光谱监测计划，并使用全球毫米波VLBI阵列（GMVA）对极端耀变体样本进行无线电干涉高分辨率成像研究。Effelsberg项目将描述TeV耀变体的射电变异性及其微弱的极化发射，为确定其从射电到TeV伽马波段的动态宽带发射提供数据。这将使我们能够确定TeV伽玛射线发射的起源位置。GMVA观测将提供亚秒差距尺度的特征结构细节，如由伽马射线发射模型预测的喷流翼变亮，并将在通过mm-VLBI可获得的最紧凑喷流尺度上对亮度、温度、核心光谱和喷流速度进行系统研究，最终将极端耀变体与其他类型的tev发射耀变体进行比较。

Extreme blazars represent a sub-class of active galaxies with collimated relativistic plasma jets, whose emission maxima range to higher energies by several orders of magnitude as compared to 'regular' blazars, reaching far into the TeV gamma-ray regime. Although only a small number of extreme blazars is known today, it is clear that they represent a numerous class of objects of high relevance for the upcoming decade of research in high-energy astronomy and astropartiale physics. Extreme blazars are of particular interest in the context of the still not understood sources of ultrahigh-energy cosmic rays and their associated processes of extreme particle acceleration, as well as possible sources of high-energy astrophysical neutrinos. The radio regime offers unprecedented possibilities of high angular-resolution imaging and high-sensitivity spectral flux-density studies to probe the structure and dynamical processes in such relativistic plasma jets. The radio emission of extreme blazars is comparatively faint and not yet well studied. In this project, we will combine a new long-term spectral monitoring program of TeV-blazars using the Effelsberg 100-m radio telescope with a radio-interferometric high-resolution imaging study of a sample of extreme blazars with the global Millimeter VLBI Array (GMVA). The Effelsberg program will characterize the radio variability properties of TeV blazars and their faint polarized emission, providing data to determine their dynamic broadband emission from the radio to the TeV-gamma regime. This will allow us to constrain the site of origin of the TeV gamma-ray emission. The GMVA observations will provide sub-parsec-scale details on characteristic structures such as jet limb brightening, predicted by gamma-ray emission models, and will yield a systematic study of brightness temperatures, core spectra and jet velocities on the most compact scales of the jets that are accessible via mm-VLBI, ultimately comparing extreme blazars with other classes of TeV-emitting blazars.