Building a GRAVITY+ Adaptive Optics Test Bench

The Gravity Plus Consortium; Florentin Millour; Philippe Berio; Stéphane Lagarde; Sylvie Robbe-Dubois; Carole Gouvret; Olivier Lai; Fatmé Allouche; Christophe Bailet; Olivier Boebion; Marcel Carbillet; Aurélie Marcotto; Alain Spang; Paul Girard; Nicolas Mauclert; Jean-Baptiste Le Bouquin; Thibaut Paumard; Ferréol Soulez; Julien Woillez; Nikhil More; Frank Eisenhauer; Christian Straubmeier; Laura Kreidberg; Paulo J. V. Garcia; Sebastian Hoenig

arXiv · 2208.11360

Building a GRAVITY+ Adaptive Optics Test Bench

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Abstract

We present the testbench aimed at integrating the GRAVITY+ adaptive optics GPAO. It consists of two independent elements, one reproducing the Coud{\'e} focus of the telescope, including the telescope deformable mirror mount (with its surface facing down), and one reproducing the Coud{\'e} room opto-mechanical environment, including a downwards-propagating beam, and the telescope mechanical interfaces in order to fit in the new GPAO wavefront sensor. We discuss in this paper the design of this bench and the solutions we adopted to keep the cost low, keep the design compact (allowing it to be fully contained in a 20 sqm clean room), and align the bench independently from the adaptive optics. We also discuss the features we have set in this bench.

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The Gravity Plus Consortium, Florentin Millour, Philippe Berio, Stéphane Lagarde, Sylvie Robbe-Dubois, Carole Gouvret, Olivier Lai, Fatmé Allouche, Christophe Bailet, Olivier Boebion, Marcel Carbillet, Aurélie Marcotto, Alain Spang, Paul Girard, Nicolas Mauclert, Jean-Baptiste Le Bouquin, Thibaut Paumard, Ferréol Soulez, Julien Woillez, Nikhil More, Frank Eisenhauer, Christian Straubmeier, Laura Kreidberg, Paulo J. V. Garcia, Sebastian Hoenig. 2022-08-24. Building a GRAVITY+ Adaptive Optics Test Bench. https://arxiv.org/abs/2208.11360

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