The calibration procedure of the LINC-NIRVANA ground and high layer WFS

Carmelo Arcidiacono; Kalyan Kumar Radhakrishnan Santhakumari; Valentina Viotto; Maria Bergomi; Florian Briegel; Thomas Bertram; Luca Marafatto; Tom Herbst; Jacopo Farinato; Roberto Ragazzoni; Ralph Hofferbert; Martin Kuerster; Frank Kittman; Juergen Berwein; Harald Baumeister

arXiv · 1807.01657

The calibration procedure of the LINC-NIRVANA ground and high layer WFS

Carmelo Arcidiacono·Kalyan Kumar Radhakrishnan Santhakumari·Valentina Viotto·Maria Bergomi·Florian Briegel·Thomas Bertram·Luca Marafatto·Tom Herbst·Jacopo Farinato·Roberto Ragazzoni·Ralph Hofferbert·Martin Kuerster·Frank Kittman·Juergen Berwein·Harald Baumeister

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Abstract

LINC--NIRVANA (LN) is an MCAO module currently mounted on the Rear Bent Gregorian focus of the Large Binocular Telescope (LBT). It mounts a camera originally designed to realize the interferometric imaging focal station of the telescopes. LN follows the LBT binocular strategy having two twin channels: a double Layer Oriented Multi-Conjugate Adaptive Optics system assisting the two arms, supplies high order wave-front correction. In order to counterbalance the field rotation, a mechanical derotation is applied for the two ground wave-front sensors, and an optical (K-mirror) one for the two high layers sensors, fixing the positions of the focal planes with respect to the pyramids aboard the wavefront sensors. The derotation introduces a pupil images rotation on the wavefront sensors, changing the projection of the deformable mirrors on the sensor consequently.

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Carmelo Arcidiacono, Kalyan Kumar Radhakrishnan Santhakumari, Valentina Viotto, Maria Bergomi, Florian Briegel, Thomas Bertram, Luca Marafatto, Tom Herbst, Jacopo Farinato, Roberto Ragazzoni, Ralph Hofferbert, Martin Kuerster, Frank Kittman, Juergen Berwein, Harald Baumeister. 2018-07-04. The calibration procedure of the LINC-NIRVANA ground and high layer WFS. https://arxiv.org/abs/1807.01657

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