SciSim is a complete simulator for the XMM-Newton X-ray observatory. Its purpose is to generate realistic simulated science data for a wide range of observational scenarios. SciSim is comprised of a number of separate simulators for the various components of the telescope and instruments on the XMM-Newton satellite. These act behind a Cosmic Simulator (CSIM), which allows the user to create source data, either through extracting sources from a catalogue, placing sources manually or simulating the sky. A ray generator (GSIM) generates data from the source for ray tracing, which is then fed down a pipeline formed by the spacecraft and instrument simulators. A fully configurable detailed physical description of all components, spacecraft, mirrors, gratings and CCD cameras, together with their interactions with X-rays, provide the means to perform deep simulation studies. The output of the simulations can be converted into a format compatible with the XMM-Newton Science Analysis System, and thus may be reduced in an identical manner to a real sky observation.
The aim of the system is multiple: to develop observation strategies, to understand calibration effects and eventual aging / malfunction of the different components, to optimize analysis tools and algorithms and as an astrometry aided tool, that can be used during mission planning phases.