092149

Very High Energy (VHE and amp gt 50 GeV) gamma rays provide a direct view of the mostextreme environments inour Galaxy and are an excellent probe of non-thermal astrophysical processes.Studies of the non-thermal Galacticsource population are essential to understand where and how the bulk of thecosmic rays are accelerated in ourGalaxy. Fermi has produced the first uniform survey of the entire Galactic planeat and amp gt 50GeV detecting more than25% unidentified sources. We propose to observe with XMM-Newton the 2 spectrallyharder and thus most extreme objects in the Fermi sample. The study of these sources with XMM-Newton will unveil new sites of particle acceleration and will allow us to understand the physics behind VHE emitters. [truncated! Please see actual data for full text]