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arXiv · 2602.07448

Sunrise III: The Wavefront Correction System

Thomas Berkefeld·Alexander Bell·Reiner Volkmer·Frank Heidecke·Tobias Preis·Thomas Sonner·Eiji Nakai·Andreas Korpi-Lagg·Achim Gandorfer·Sami K. Solanki·Jose Carlos del Toro Iniesta·Yukio Katsukawa·Pietro Bernasconi·Alex Feller·Tino L. Riethmüller·Alberto Álvarez-Herrero·Masahito Kubo·Valentín Martínez Pillet·H. N. Smitha·David Orozco Suárez·Bianca Grauf·Michael Carpenter
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Abstract

This paper describes the wave-front correction and image stabilisation system (CWS) developed for the Sunrise III balloon-borne telescope, and provides information about its performance as measured during the integration into the telescope and during the 2024 science flight. The fast image stabilisation is done by a correlation tracker (CT) and a fast tip-tilt mirror, low order aberrations such as defocus and coma are measured by a six-element Shack-Hartmann wavefront sensor (WFS) and corrected by an active telescope secondary mirror for automated focus and manual coma correction. The CWS is specified to deliver a stabilised image with a precision of 0.005 arcsec (rms). The autofocus adjustment is specified to maintain a focus stability of 0.01 waves in the focal plane of the CWS.

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Thomas Berkefeld, Alexander Bell, Reiner Volkmer, Frank Heidecke, Tobias Preis, Thomas Sonner, Eiji Nakai, Andreas Korpi-Lagg, Achim Gandorfer, Sami K. Solanki, Jose Carlos del Toro Iniesta, Yukio Katsukawa, Pietro Bernasconi, Alex Feller, Tino L. Riethmüller, Alberto Álvarez-Herrero, Masahito Kubo, Valentín Martínez Pillet, H. N. Smitha, David Orozco Suárez, Bianca Grauf, Michael Carpenter. 2026-02-07. Sunrise III: The Wavefront Correction System. https://doi.org/10.1007/s11207-026-02649-7

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