25 January 2016 Exoplanet detection and characterization via parallel broadband nulling coronagraphy
Author Affiliations +
Abstract
The contrast and angular resolution required to directly image and characterize mature exoplanetary systems place stringent requirements on the space-based telescopes and starlight suppression systems needed to study spatial distributions of debris disks, exozodiacal dust, and individual planets at multiple epochs in their orbits. A nulling interferometer (nuller) is a coronagraphic suppression system that can be used with all telescope types, including those with obscured and segmented apertures envisioned for upcoming and future observatories. One of the challenges for detection and characterization of exoplanetary signals is achieving high contrast with broad spectral coverage. This work presents design concepts for broadband nulling over four parallel ∼20% bandpasses spanning the visible spectrum. Contrast-limiting effects of stellar angular extent, residual chromaticity of broadband phase shifters, and aperture diffraction are considered to reach simultaneous ≲2×10−8 contrast over separations spanning 0.2 to 0.9 arc sec for a 2.4-m telescope observing a Sun-like star at 10 pc. With added dark hole wavefront control and postprocessing point spread function subtraction techniques to further reduce scattered starlight, such a system could be capable of detecting the very the nearest Earth-like exoplanets and spectral characterization of several nearby extrasolar gas giants.
© 2016 Society of Photo-Optical Instrumentation Engineers (SPIE) 2329-4124/2016/$25.00 © 2016 SPIE
Brian A. Hicks "Exoplanet detection and characterization via parallel broadband nulling coronagraphy," Journal of Astronomical Telescopes, Instruments, and Systems 2(1), 011015 (25 January 2016). https://doi.org/10.1117/1.JATIS.2.1.011015
Published: 25 January 2016
Lens.org Logo
CITATIONS
Cited by 24 scholarly publications.
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Nulling interferometry

Coronagraphy

Space telescopes

Telescopes

Point spread functions

Stars

Wavefronts

Back to Top