Apodized Pupil Lyot Coronagraphs for arbitrary apertures. V. Hybrid shaped pupil designs for imaging earth-like planets with future space observatories

Journal Article · Sat Feb 20 04:00:00 EST 2016 · Astrophysical Journal

DOI:https://doi.org/10.3847/0004-637X/818/2/163· OSTI ID:22886999

N’Diaye, Mamadou; Soummer, Rémi; Pueyo, Laurent; Stark, Christopher C.; Perrin, Marshall D. ^[1]; Carlotti, Alexis ^[2]

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1. Space Telescope Science Institute, 3700 San Martin Drive, 21218 Baltimore MD (United States)
2. CNRS, IPAG, F-38000 Grenoble (France)

We introduce a new class of solutions for Apodized Pupil Lyot Coronagraphs (APLC) with segmented aperture telescopes to remove broadband diffracted light from a star with a contrast level of 10{sup 10}. These new coronagraphs provide a key advance to enabling direct imaging and spectroscopy of Earth twins with future large space missions. Building on shaped pupil (SP) apodization optimizations, our approach enables two-dimensional optimizations of the system to address any aperture features such as central obstruction, support structures, or segment gaps. We illustrate the technique with a design that could reach a 10{sup 10} contrast level at 34 mas for a 12 m segmented telescope over a 10% bandpass centered at a wavelength of λ{sub 0} = 500 nm. These designs can be optimized specifically for the presence of a resolved star and, in our example, for stellar angular size up to 1.1 mas. This would allow one to probe the vicinity of Sun-like stars located beyond 4.4 pc, therefore, fully retiring this concern. If the fraction of stars with Earth-like planets is η{sub ⊕}=0.1, with 18% throughput, assuming a perfect, stable wavefront and considering photon noise only, 12.5 exo-Earth candidates could be detected around nearby stars with this design and a 12 m space telescope during a five-year mission with two years dedicated to exo-Earth detection (one total year of exposure time and another year of overheads). Our new hybrid APLC/SP solutions represent the first numerical solution of a coronagraph based on existing mask technologies and compatible with segmented apertures, and that can provide contrast compatible with detecting and studying Earth-like planets around nearby stars. They represent an important step forward toward enabling these science goals with future large space missions.

• OSTI ID: 22886999
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 818; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United Kingdom
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
NUMERICAL SOLUTION
PLANETS
RESOLUTION
SPACE
SPECTROSCOPY
SUN
TELESCOPES
TWO-DIMENSIONAL CALCULATIONS