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NASA NTRS · 20140002114

End-to-end Coronagraphic Modeling Including a Low-order Wavefront Sensor

Krist, John E.·Trauger, John T.·Unwin, Stephen C.·Traub, Wesley A.
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Abstract

To evaluate space-based coronagraphic techniques, end-to-end modeling is necessary to simulate realistic fields containing speckles caused by wavefront errors. Real systems will suffer from pointing errors and thermal and motioninduced mechanical stresses that introduce time-variable wavefront aberrations that can reduce the field contrast. A loworder wavefront sensor (LOWFS) is needed to measure these changes at a sufficiently high rate to maintain the contrast level during observations. We implement here a LOWFS and corresponding low-order wavefront control subsystem (LOWFCS) in end-to-end models of a space-based coronagraph. Our goal is to be able to accurately duplicate the effect of the LOWFS+LOWFCS without explicitly evaluating the end-to-end model at numerous time steps.

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Krist, John E., Trauger, John T., Unwin, Stephen C., Traub, Wesley A.. 2012-07-01. End-to-end Coronagraphic Modeling Including a Low-order Wavefront Sensor. https://ntrs.nasa.gov/citations/20140002114

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