Begin Dome seeing is a critical effect influencing the optical performance of ground based telescopes. A previously reported combination of Computational Fluid Dynamics (CFD) and optical simulations to model dome seeing was implemented for the latest LSST enclosure geometry. To this end, high spatial resolution thermal unsteady CFD simulations were performed for three different telescope zenith angles and four azimuth angles. These simulations generate time records of refractive index values along the optical path, which are post-processed to estimate the image degradation due to dome seeing. This method allows us to derive the distribution of seeing contribution along the different optical path segments that composed the overall light path between the entrance of the dome up to the LSST science camera. These results are used to recognize potential problems and to guide the observatory design. In this paper, the modeling estimates are reviewed and assessed relative to the corresponding performance allocation, and combined with other simulator outputs to model the dome seeing impact during LSST operations.

Date Published: 4 August 2014
PDF: 10 pages
Proc. SPIE 9150, Modeling, Systems Engineering, and Project Management for Astronomy VI, 91500R (4 August 2014); doi: 10.1117/12.2054436

Published in SPIE Proceedings Vol. 9150:
Modeling, Systems Engineering, and Project Management for Astronomy VI
George Z. Angeli; Philippe Dierickx, Editor(s)