LABORATORY TESTS OF EDDINGTON PHOTOMETRY

摘要

The Eddington imaging photometer will operate in a challenging regime in terms of stability (detecting variations down to ～ 1 part in 10~4). Therefore, careful laboratory tests will be required to ensure that the detectors and associated electronics are capable of meeting this specification and others derived from the science requirements. Such testing will be required throughout the definition, implementation and mission phases. Initially, tests on preliminary CCDs will be performed to confirm their suitability. During the implementation phase, tests will be necessary on the various instrument models to verify the performance of CCDs and electronics combined. During the mission phase, further lab tests will be needed using flight-representative hardware to understand the performance of the flight instrument in flight conditions. To this end, MSSL. is developing a suitable test bench to support these activities. The parameters and performance of the test bench are described and recent results shown. Three particular areas of concern for Eddington are being addressed in the work presented here: 1. detection of 10~(-4) variations; 2. observation of bright sources. Several asteroseismology target sources exist (V～ 3) which will exceed the CCD full-well capacity in normal operation; 3. crowded fields. Strategies and results are presented in each of these areas.