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This book uses new data from the very low radio frequency telescope LOFAR to analyse the magnetic structure in the giant radio galaxy NGC6251. This analysis reveals that the magnetic field strength in the locality of this giant radio galaxy is an order of magnitude lower than in other comparable systems. Due to the observational limitations associated with capturing such huge astrophysical structures, giant radio galaxies are historically a poorly sampled population of objects; however, their preferential placement in the more rarefied regions of the cosmic web makes them a uniquely important probe of large-scale structures. In particular, the polarisation of the radio emissions from giant radio galaxies is one of the few tools available to us that can be used to measure magnetic fields in regions where the strength of those fields is a key differentiator for competing models of the origin of cosmic magnetism. Low frequency polarisation data are crucial for detailed analyses of magnetic structure, but they are also the most challenging type of observational data to work with. This book presents a beautifully coupled description of the technical and scientific analysis required to extract valuable information from such data and, as the new generation of low frequency radio telescopes reveals the larger population of giant radio galaxies, it offers a significant resource for future analyses.

Radio Galaxies: Radiation Transfer, Dynamics, Stability and Evolution of a Synchrotron Plasmon deals with the physics of a region in space containing magnetic field and thermal and relativistic particles (a plasmon). The synchrotron emission and absorption of this region are discussed, along with the properties of its spectrum; its linear and circular polarization; transfer of radiation through such a region; its dynamics and expansion; and interaction with external medium. Comprised of eight chapters, this volume explores the stability, turbulence, and acceleration of particles in a synchrotron plasmon as well as its application to the physics of radio galaxies. The discussion begins with a description of extragalactic radio sources and their properties, followed by an analysis of the emission and absorption of synchrotron radiation. Subsequent chapters focus on the transfer of polarized radiation in a magnetoactive plasma; hydromagnetics and hydromagnetic stability; confinement and structure of extended radio sources; and radio-tail galaxies. The book also considers compact radio sources before concluding with an evaluation of radio source theories. This monograph is addressed primarily to radio astronomers and graduate students working on the interpretation of observational data.