JWST fine guidance sensor - guiding performance analysis

摘要

The Engineering Test Unit (ETU) of the Fine Guidance Sensor (FGS) for the James Webb Space Telescope (JWST) is currently in fabrication. Extensive modeling of the key FGS-Guider performance parameters has been used throughout the design process and continues to be used to evaluate the expected performance of the as-built instrument. A key parameter of interest is the expected Noise Equivalent Angle (NEA) provided by the FGS. The NEA will, in part, determine the ultimate image quality of the JWST Observatory. In this paper we use updated estimates of the End-of-life impact of contamination to present the current expected NEA performance of the FGS flight model. As component test data becomes available this data will be used as input to the FGS NEA performance model to assess the expected performance of the instrument.