Structure Flows, AGN and the WHIM

琼斯博士和鲁德尼克博士将进行磁流体动力学（MHD）模拟和无线电观测的协调计划，以研究温热星系际介质（WHIM）。在早期宇宙中，低密度气体与暗物质混合在一起。当密度过大的区域坍塌形成“宇宙网”的细丝时，气体以超音速落入这些细丝中，在那里被冲击波加热并电离形成WHIM。磁场将在冲击中被放大，电子将加速到相对论速度。这个团队的目标是通过它的极化无线电同步辐射来探测丝状WHIM。他们将把注意力集中在红移z ~ 0.1的地方，这个距离足够远，以至于WHIM细丝看起来足够窄，足以将它们与银河系前景区分开来，后者在大于一度的角尺度上占主导地位。该团队将使用MHD模拟来跟踪巨型射电星系在百万秒差距尺度上撞击WHIM时的流出，包括对宇宙射线加速和传输的自一致处理。模拟的物体将与从无线电到伽马射线的整个光谱中观测到的结构进行比较，以测试WHIM和星系间磁场起源的模型。两名研究生将与本科生一起参与这项研究。该团队将访问学校、教堂、民间组织和州立公园，分享有关基础天文学的信息以及他们自己的研究。

Dr. Jones and Dr. Rudnick will conduct a coordinated program of magnetohydrodynamic (MHD) simulations and radio observations to study the Warm-Hot Intergalactic Medium (WHIM). In the early Universe, low-density gas is mixed with dark matter. As over-dense regions collapse to form the filaments of the 'cosmic web', the gas falls supersonically into these filaments, where it is shock-heated and ionized to form the WHIM. Magnetic fields will be amplified in the shocks, and electrons accelerated to relativistic speeds. This team aims to detect the filamentary WHIM by its polarized radio synchrotron radiation. They will concentrate on a redshift z ~ 0.1, just distant enough that the WHIM filaments appear narrow enough to distinguish them from the Galactic foreground, which predominates on angular scales larger than a degree across. The team will use MHD simulations to follow outflows from giant radio galaxies over megaparsec scales as they impinge on the WHIM, including a self-consistent treatment of cosmic ray acceleration and transport. The simulated objects will be compared to observed structures over the whole spectrum from radio to gamma-rays, to test models for the WHIM and the origin of intergalactic magnetic fields.Two graduate students will be trained by participating in the research, along with undergraduate students. The team will visit schools, churches, civic organizations and state parks to share information about basic astronomy as well as their own research.