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arXiv · 2506.03721

GRAVITY+ adaptive optics (GPAO) tests in Europe

Florentin Millour·Guillaume Bourdarot·Jean-Baptiste Le Bouquin·Anthony Berdeu·Mathis Houllé·Philippe Berio·Thibaut Paumard·Denis Defrère·Paulo Garcia·Ferreol Soulez·Sebastian Hoenig·Fatmé Allouche·Martin Bachbucher·Christophe Bailet·Cyrille Blanchard·Olivier Boebion·Henri Bonnet·Amit Brara·Marcel Carbillet·Stephan Czempiel·Alain Delboulbé·Roderick Dembet·Clémence Edouard·Frank Eisenhauer·Halmut Feuchtgruber·Christoph Furchstsam·Stefan Gillessen·Armin Goldbrunner·Tiago Gomes·Carole Gouvret·Sylvain Guieu·Michael Hartl·Johannes Hartwig·Frank Haussmann·David Huber·Ihsan Ibn Taïeb·Johann Kolb·Stéphane Lagarde·Olivier Lai·James Leftley·Dieter Lutz·Yves Magnard·Hugo Nowacki·Sylvain Oberti·Thomas Ott·Christian Rau·Sylvie Robbe-Dubois·Jules Scigliuto·Franz Soller·Pavel Shchekaturov·Daniel Schuppe·Eric Stadler·Sinem Uysal·Felix Widmann·Ekherhard Wieprecht·Julien Woillez·Senol Yazici
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Abstract

We present in this proceeding the results of the test phase of the GRAVITY+ adaptive optics. This extreme AO will enable both high-dynamic range observations of faint companions (including exoplanets) thanks to a 40x40 sub-apertures wavefront control, and sensitive observations (including AGNs) thanks to the addition of a laser guide star to each UT of the VLT. This leap forward is made thanks to a mostly automated setup of the AO, including calibration of the NCPAs, that we tested in Europe on the UT+atmosphere simulator we built in Nice. We managed to reproduce in laboratory the expected performances of all the modes of the AO, including under non-optimal atmospheric or telescope alignment conditions, giving us the green light to proceed with the Assembly, Integration and Verification phase in Paranal.

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Florentin Millour, Guillaume Bourdarot, Jean-Baptiste Le Bouquin, Anthony Berdeu, Mathis Houllé, Philippe Berio, Thibaut Paumard, Denis Defrère, Paulo Garcia, Ferreol Soulez, Sebastian Hoenig, Fatmé Allouche, Martin Bachbucher, Christophe Bailet, Cyrille Blanchard, Olivier Boebion, Henri Bonnet, Amit Brara, Marcel Carbillet, Stephan Czempiel, Alain Delboulbé, Roderick Dembet, Clémence Edouard, Frank Eisenhauer, Halmut Feuchtgruber, Christoph Furchstsam, Stefan Gillessen, Armin Goldbrunner, Tiago Gomes, Carole Gouvret, Sylvain Guieu, Michael Hartl, Johannes Hartwig, Frank Haussmann, David Huber, Ihsan Ibn Taïeb, Johann Kolb, Stéphane Lagarde, Olivier Lai, James Leftley, Dieter Lutz, Yves Magnard, Hugo Nowacki, Sylvain Oberti, Thomas Ott, Christian Rau, Sylvie Robbe-Dubois, Jules Scigliuto, Franz Soller, Pavel Shchekaturov, Daniel Schuppe, Eric Stadler, Sinem Uysal, Felix Widmann, Ekherhard Wieprecht, Julien Woillez, Senol Yazici. 2025-06-04. GRAVITY+ adaptive optics (GPAO) tests in Europe. https://doi.org/27e8%3B10.1117/12.3020269

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