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arXiv · 1405.0824

On-sky speckle nulling demonstration at small angular separation with SCExAO

Frantz Martinache·Olivier Guyon·Nemanja Jovanovic·Christophe Clergeon·Garima Singh·Tomoyuki Kudo·Thayne Currie·Christian Thalmann·Michael McElwain·Motohide Tamura
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Abstract

This paper presents the first on-sky demonstration of speckle nulling, which was achieved at the Subaru Telescope in the context of the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) Project. Despite the absence of a high-order high-bandwidth closed-loop AO system, observations conducted with SCExAO show that even in poor-to-moderate observing conditions, speckle nulling can be used to suppress static and slow speckles even in the presence of a brighter dynamic speckle halo, suggesting that more advanced high-contrast imaging algorithms developed in the laboratory can be applied to ground-based systems.

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Frantz Martinache, Olivier Guyon, Nemanja Jovanovic, Christophe Clergeon, Garima Singh, Tomoyuki Kudo, Thayne Currie, Christian Thalmann, Michael McElwain, Motohide Tamura. 2014-05-05. On-sky speckle nulling demonstration at small angular separation with SCExAO. https://doi.org/10.1086/677141

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