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arXiv · 1109.6047

Kernel-phases for high-contrast detection beyond the resolution limit

Frantz Martinache
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Abstract

The detection of high contrast companions at small angular separation appears feasible in conventional direct images using the self-calibration properties of interferometric observable quantities. In the high-Strehl regime, available from space borne observatories and using AO in the mid-infrared, quantities comparable to the closure-phase that are used with great success in non-redundant masking inteferometry, can be extracted from direct images, even taken with a redundant aperture. These new phase-noise immune observable quantities, called Kernel-phases, are determined a-priori from the knowledge of the geometry of the pupil only. Re-analysis of HST/NICMOS archive and other ground based AO images, using this new Kernel-phase algorithm, demonstrates the power of the method, and its ability to detect companions at the resolution limit and beyond.

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Frantz Martinache. 2011-09-27. Kernel-phases for high-contrast detection beyond the resolution limit. https://doi.org/10.1117/12.894319

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