Milliarcsecond Polarization Measurements of Compact Extragalactic Radio Sources

该奖项资助了在最小尺度上研究活动星系核(AGN)厘米波长辐射的线性偏振。这将通过偏振敏感甚长基线干涉测量(VLBI)技术来实现，从而可以在多个波长上以毫角秒的角度尺度确定紧凑型射电源的线性偏振结构。罗伯茨博士是VLBI极化研究的先驱和主要研究者之一。在活动星系核的距离上，这些小的角度尺度对应于光年的物理尺度。线偏振告诉我们AGN产生的射电喷流的磁场结构、辐射机制、粒子含量、运动学和几何形状，这将有助于我们了解它们的结构和演化。这项工作的最终目标是了解活动星系核的核心机制，目前认为活动星系核是在大质量黑洞上吸积。

This award funds a study of the linear polarization of the centimeter wavelength radiation from Active Galactic Nuclei (AGN) on the smallest scales. This is to be accomplished with the technique of polarization sensitive Very Long Baseline Interferometry (VLBI), whereby the linear polarization structure of compact radio sources may be determined on angular scales of milliarcseconds at multiple wavelengths. Dr. Roberts is one of the pioneers and leading investigators in VLBI polarization studies. At the distances of AGN, these small angular scales correspond to physical scales of light years. The linear polarization tells us about the magnetic field structure, radiation mechanisms, particle content, kinematics, and geometry of the radio jets produced by AGN, which will help us understand their structure and evolution. The ultimate goal of this work is to understand the mechanism which lies at the heart of AGN, currently thought to be accretion onto massive black holes.