Shocks in groups

High resolution Xray data of IC1262 and Stephan.s Quintet haverevealed features with unusual morphologies that are interpreted in theframework of shockheating of the intergalactic gas as a result ofinfall of new material, interaction and/or merging phenomena.These 2 groups have significantly different properties: IC1262 is Spiralpoorand apparently unperturbed, Stephan.s Quintet is Spiralrich anddisplays strong signs of dynamical interaction. We propose XMM observationsthat will allow us to study the spectral properties of the shock features to better understand their nature. The comparison between them will enable usto further our understanding of environmental dependencies and/or evolutionary phases in the formation and evolution of poor groups. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]