Abstract
Pupil mapping is a technique whereby a uniformly illuminated input pupil, such as from starlight, can be mapped into a nonuniformly illuminated exit pupil, such that the image formed from this pupil will have suppressed sidelobes, many orders of magnitude weaker than classical Airy ring intensities. Pupil mapping is therefore a candidate technique for coronagraphic imaging of extrasolar planets around nearby stars. Unlike most other high-contrast imaging techniques, pupil mapping is lossless and preserves the full angular resolution of the collecting telescope. So it could possibly give the highest signal-to-noise ratio of any proposed single-telescope system for detecting extrasolar planets. Prior analyses based on pupil-to-pupil ray-tracing indicate that a planet fainter than 10-10 times its parent star, and as close as about 2λ/D, should be detectable. In this paper we describe the results of careful diffraction analysis of pupil-mapping systems. These results reveal a serious unresolved issue. Namely, high-contrast pupil mappings distribute light from very near the edge of the first pupil to a broad area of the second pupil, and this dramatically amplifies diffraction-based edge effects, resulting in a limiting attainable contrast of about 10-5. We hope that by identifying this problem, others will provide a solution.
Original language | English (US) |
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Pages (from-to) | 528-543 |
Number of pages | 16 |
Journal | Astrophysical Journal |
Volume | 636 |
Issue number | 1 I |
DOIs | |
State | Published - Jan 1 2006 |
Externally published | Yes |
All Science Journal Classification (ASJC) codes
- Astronomy and Astrophysics
- Space and Planetary Science
Keywords
- Planetary systems
- Techniques: high angular resolution