Relativistic Plasma Probes of Low Overdensity Environments

低z宇宙中的大部分重子位于难以观测的气体低密度环境中，其中包含有关宇宙网演化的关键信息。越来越多的人认识到，这种演化在很大程度上受到磁化相对论性粒子群的影响，即相对论性等离子体。这些等离子体的同步加速器和非热x射线发射也可以作为环境物理条件的独特观测诊断。这个项目是对这些相对论性等离子体及其与周围热等离子体相互作用的一套雄心勃勃的理论和观测研究。它包括：使用旋转测量综合对星系细丝因落入而产生的冲击进行调查；利用射电星系测量低星系和重子密度区域的局地压力；通过同步辐射微晕的研究探索群内介质；首次在现实的非均匀低密度宇宙环境中对射电星系演化进行三维模拟，包括磁场和辐射相对论等离子体；研究宇宙射线在大尺度宇宙结构激波和超风末端激波中的发射，包括流动的非线性反馈和相关的MHD湍流。将独特的多维MHD模拟与真实的合成观测相结合，将确定适用于实际观测的最佳物理分析方法。观察和理论工作之间的协同作用将大大提高从各自获得的见解的价值。这项研究将培养本科生和研究生在前沿科学和创新的数据分析和数值模拟技术的发展。该团队致力于传播他们的成果，包括与当地天文馆、K-12公立学校和社区团体合作。

AST-0607674JonesA large fraction of baryons in the low-z universe reside in hard-to-observe gaseous low-density settings, which contain crucial information about the evolution of the cosmic web. There is an increasing appreciation that this evolution is heavily influenced by magnetized relativistic particle populations, that is, relativistic plasmas. Synchrotron and non-thermal X-ray emissions from these plasmas also serve as unique observational diagnostics of environmental physical conditions. This project is an ambitious suite of theoretical and observational studies of these relativistic plasmas and their interactions with the surrounding thermal plasmas. It includes: a survey of filaments of galaxies for shocks due to infall, using rotation measure synthesis; measuring the local pressures in regions of low galactic and baryon density using radio galaxies; exploring the intra-group medium through studies of mini-halos of synchrotron radiation; the first 3D simulations of radio galaxy evolution, including magnetic fields and radiant relativistic plasmas, in realistic, inhomogeneous low density cosmological environments; and investigation of emissions from cosmic rays in large scale cosmic structure shocks and in super-wind terminal shocks, including nonlinear feedback on flows and associated MHD turbulence. The combination of unique multidimensional MHD simulations with realistic synthetic observations will identify the optimal physical analysis methods to apply to real observations. The synergy between the observational and theoretical efforts will greatly enhance the value of the insights to be gained from each alone.This research will train undergraduate and graduate students in both cutting edge science and the development of innovative data analysis and numerical simulation techniques. The team has a commitment to spreading their results, including work with the local planetarium, K-12 public schools, and community groups.