Jet Feedback on Groups and Galaxy Clusters

宇宙学和谐模型提供了一个惊人的匹配大尺度宇宙学调查的数据，但在较小的尺度上，重子效应开始成为主导，情况就不那么清楚了。特别是，晕质量和星系光度分布显着不同，使星星转换效率是一个很强的函数晕质量。气体转化为恒星的效率较低，接近星系群和星系团的规模。 冷却气体、随后的星星形成和核活动的相互作用似乎与一个自我调节的反馈回路紧密相连，这可能解释这个宇宙学难题。该项目的主要目标是研究喷流附近活动星系核反馈回路的非热方面，并比较观测到的和合成的无线电发射，以校准反馈。 为此，该项目利用LOFAR数据（特别是新获得的高分辨率长基线数据）和最先进的宇宙学磁流体动力学模拟，利用星系群和星系团的宇宙射线和活动星系核喷流物理学，探索喷流如何将能量和动量转移到星系团内介质，并调节冷却和星星形成。从这个项目的结果作为大规模的限制，小规模的相对论射流模型，将在这个拟议的研究单位，特别是由墨卡托研究员Manel Perucho追求。 我们的主要研究问题是：1.反馈能量是如何从活动星系核喷流转移到冷却的ICM的？哪些观测信号明确地证明了这一点？2.来自活动星系核喷流的宇宙线加热能再现所观察到的冷核和非冷核星团分布的双峰性吗？3.哪些参数决定了活动星系核喷流的形态（光度、环境或成分）？我们如何将其与反馈联系起来？

The cosmological concordance model provides an astonishing match to data of large-scale cosmological surveys, but on smaller scales—where baryonic effects start to become dominant— the situation is less clear. In particular, the halo mass and galaxy luminosity distributions differ significantly so that the star conversion efficiency has to be a strong function of halo mass. Gas is less efficiently converted to stars towards the scale of galaxy groups and clusters. The interplay of cooling gas, subsequent star formation, and nuclear activity appears to be tightly coupled to a self-regulated feedback loop that may explain this cosmological conundrum. The main goal of this project aims at studying the non-thermal aspect of the active galactic nucleus (AGN) feedback loop in the vicinity of the jet and compares observed and synthetic radio emission to calibrate feedback. To this end, this project uses LOFAR data (in particular newly available high-resolution long-baseline data) and state-of-the-art cosmological magneto-hydrodynamical simulations with cosmic ray and AGN jet physics of galaxy groups and clusters to explore how jets transfer energy and momentum to the intracluster medium (ICM) and regulate cooling and star formation. Results from this project serve as large-scale constraints to small-scale relativistic jet models that will be pursued in this proposed research unit in particular by the Mercator fellow Manel Perucho. Our main research questions are: 1. How is feedback energy transferred from the AGN jets to the cooling ICM and which observational signatures demonstrate this unambiguously? 2. Can cosmic ray heating from AGN jets reproduce the observed bimodality of the distribution of cool core and non-cool core clusters? 3. Which parameters determine the morphology of AGN jets (luminosity, environment, or composition) and how can we relate this to feedback?