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arXiv · 2607.29438

Charge migration characterization in the METIS H2RG detectors

Danny Gasman·Benoît Serra·Roy van Boekel·Ioannis Argyriou·Daniel Dicken·Vianak Naranjo·Peter Bizenberger
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Abstract

The Mid-infrared ELT Imager and Spectrograph (METIS) is one of the first-light instruments of the Extremely Large Telescope (ELT). For the L and M band, the instrument makes use of Teledyne's H2RG detectors, known to be affected by charge migration, also known as the brighter-fatter effect (BFE). In the H2RG detectors this manifests as photo-electrons moving from a central bright pixel to neighboring pixels as the depletion region of the central pixel shrinks with accumulated charge. Due to its effect of `blurring' information, it especially affects direct imaging, transit, and high-resolution spectroscopy applications. We aim to characterize its effect in the METIS H2RG detectors, such that we can remove it without losing information.

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Danny Gasman, Benoît Serra, Roy van Boekel, Ioannis Argyriou, Daniel Dicken, Vianak Naranjo, Peter Bizenberger. 2026-07-31. Charge migration characterization in the METIS H2RG detectors. https://arxiv.org/abs/2607.29438

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