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arXiv · 2208.01806

High Contrast Imaging at the Photon Noise Limit with WFS-based PSF Calibration

Olivier Guyon·Barnaby Norris·Marc-Antoine Martinod·Kyohoon Ahn·Vincent Deo·Nour Skaf·Julien Lozi·Sebastien Vievard·Sebastiaan Haffert·Thayne Currie·Jared Males·Alison Wong·Peter Tuthill
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Abstract

Speckle Noise is the dominant source of error in high contrast imaging with adaptive optics system. We discuss the potential for wavefront sensing telemetry to calibrate speckle noise with sufficient precision and accuracy so that it can be removed in post-processing of science images acquired by high contrast imaging instruments. In such a self-calibrating system, exoplanet detection would be limited by photon noise and be significantly more robust and efficient than in current systems. We show initial laboratory and on-sky tests, demonstrating over short timescale that residual speckle noise is indeed calibrated to an accuracy exceeding readout and photon noise in the high contrast region. We discuss immplications for the design of space and ground high-contrast imaging systems.

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Olivier Guyon, Barnaby Norris, Marc-Antoine Martinod, Kyohoon Ahn, Vincent Deo, Nour Skaf, Julien Lozi, Sebastien Vievard, Sebastiaan Haffert, Thayne Currie, Jared Males, Alison Wong, Peter Tuthill. 2022-08-03. High Contrast Imaging at the Photon Noise Limit with WFS-based PSF Calibration. https://arxiv.org/abs/2208.01806

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