Calibrations of the EPIC instrument<br /> onboard the XMM-Newton satellite<br />X-ray observations<br /> of Clusters of galaxies

The XMM-Newton satellite is the second of the four cornerstones on which the European Space Agency based its sky exploration program, and is aimed at opening further the X-rays window and map the high energies population from the Galaxy as well as from the deep Universe.<br /><br />Within the first part, I make a review of the high energies astrophysics current main topics, like the observations of clusters of galaxies, and summarize the context wherein such an X-ray space observatory has been brought forward. A description of the XMM-Newton X-ray telescopes is then presented in the second part, as detailed as needed by the following.<br /><br />I explain in the third part how were conducted the EPIC instruments ground calibration campaigns within the synchrotron test facility in Orsay, and the analysis of the resulting data. In the fourth part, ground calibrations results are compared to some in-flight calibrations datasets, and methods for analysing data from extended sources (like clusters of galaxies) observations are extensively described.<br /><br />Finally, my conclusions regarding future extended sources observations with XMM-Newton and relevant data analysis strategies are drawn in the light of X-rays instrumentation general perspectives as well as the development of Virtual Observatories.