High-Spectral Resolution Dark Holes: Concept, Results, and Promise

William Thompson; Adam B. Johnson; Christian Marois; Olivier Lardière; Frédéric Grandmont; Tim Hardy; Kris Caputa; Colin Bradley; Garima Singh

arXiv · 2311.01421

High-Spectral Resolution Dark Holes: Concept, Results, and Promise

William Thompson·Adam B. Johnson·Christian Marois·Olivier Lardière·Frédéric Grandmont·Tim Hardy·Kris Caputa·Colin Bradley·Garima Singh

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Abstract

Next generation high contrast imaging instruments face a challenging trade off: they will be required to deliver data with high spectral resolution at a relatively fast cadence (minutes) and across a wide field of view (arcseconds). For instruments that employ focal plane wavefront sensing and therefore require super-Nyquist sampling, these requirements cannot simultaneously be met with a traditional lenslet integral field spectrograph (IFU). For the SPIDERS pathfinder instrument, we are demonstrating an imaging Fourier transform spectrograph (IFTS) that offers a different set of tradeoffs than a lenslet IFU, delivering up to R20,000 spectral resolution across a dark hole. We present preliminary results from the SPIDERS IFTS including a chromaticity analysis of its dark hole and demonstrate a spectral differential imaging (SDI) improvement of up to 40 $\times$, and a first application of spectro-coherent differential imaging, combining both coherent differential imaging (CDI) and SDI.

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William Thompson, Adam B. Johnson, Christian Marois, Olivier Lardière, Frédéric Grandmont, Tim Hardy, Kris Caputa, Colin Bradley, Garima Singh. 2023-11-02. High-Spectral Resolution Dark Holes: Concept, Results, and Promise. https://arxiv.org/abs/2311.01421

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