The LSST Operations Simulator has established the étendue required to meet survey specifications in terms of the number of visits per filter in 10 years, time sampling, and image quality. The Simulator includes models for the weather and local seeing based on actual site measurements, the lunar cycle, telescope dynamic characteristics, downtime required for maintenance, etc. These simulations show that LSST can meet its science goals as outlined in the SRD.
The LSST Image Simulator produces 'end-to-end' image simulations to verify the scientific performance of the complete LSST system design. It inputs realistic catalogs from a range of cosmological and Galactic structure models (including the Millenium survey) creating a database of astronomical sources to a depth of r=28. Each source is represented by its astrometric, photometric, and spectral properties (including morphology, variability and spectral energy distribution). For an LSST pointing (from the Operations Simulator output) the astronomical sources are photon ray-traced through a 12 layer turbulent atmosphere , through the telescope and camera optics and converted into electrons in a simulation of the detector performance (including chip defects, charge diffusion and saturation effects).
