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arXiv · 1810.00714

Recurrence quantification analysis as a post-processing technique in adaptive optics high-contrast imaging

M. Stangalini·G. Li Causi·F. Pedichini·S. Antoniucci·M. Mattioli·J. Christou·G. Consolini·D. Hope·S. M. Jefferies·R. Piazzesi·V. Testa
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Abstract

In this work we explore the possibility of using Recurrence Quantification Analysis (RQA) in astronomical high-contrast imaging to statistically discriminate the signal of faint objects from speckle noise. To this end, we tested RQA on a sequence of high frame rate (1 kHz) images acquired with the SHARK-VIS forerunner at the Large Binocular Telescope. Our tests show promising results in terms of detection contrasts at angular separations as small as $50$ mas, especially when RQA is applied to a very short sequence of data ($2$ s). These results are discussed in light of possible science applications and with respect to other techniques like, for example, Angular Differential Imaging and Speckle-Free Imaging.

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M. Stangalini, G. Li Causi, F. Pedichini, S. Antoniucci, M. Mattioli, J. Christou, G. Consolini, D. Hope, S. M. Jefferies, R. Piazzesi, V. Testa. 2018-10-01. Recurrence quantification analysis as a post-processing technique in adaptive optics high-contrast imaging. https://doi.org/10.3847/1538-4357/aae58e

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