The dynamics of FRII giant radio sources

Giant radio sources (GRSs) raise several important questions related to theirconfinement, evolution, particle content and the properties of the IGM theyinhabit. We propose to observe 4 GRSs with {it XMM} to image and determine thespectra of their Xray emission in an attempt to address some of thesequestions. The detection of inverseCompton emission from the radio lobes willenable us to estimate lobe pressures. We will also determine any Xray emissionfrom a hotgas environment, and thus understand the properties of the externalmedium and the confinement of the radio lobes. These observations will pave theway for the use of GRSs as cosmological probes and also help us to understandthe evolution of magnetic fields and energy densities with age. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]