First light of the LINC-NIRVANA Pathfinder experiment

Bergomi, Maria; Viotto, Valentina; Arcidiacono, Carmelo; Marafatto, Luca; Farinato, Jacopo; Baumeister, Harald; Bertram, Thomas; Berwein, Jürgen; Briegel, Florian; Conrad, Albert; Kittman, Frank; Kopon, Derek; Hofferbert, R.; Magrin, Demetrio; Santhakumari, Kalyan Kumar Radhakrishnan; Puglisi, Alfio; Xompero, Marco; Briguglio, Runa; Quirós-Pacheco, Fernando; Herbst, Tom; Ragazzoni, Roberto

doi:10.1117/12.2055533

Cited by 5 publications

(4 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The complication of the rotation of the DM as seen by the WFS was solved by averaging different interaction matrix recorded at different angles. The interaction matrix computed in this way were successfully used both in the laboratory and on sky 23 and both for the GWS and HWS. As of June 2018 the LN is being commissioned 15,24 at the LBT observatory.…”

Section: Discussionmentioning

confidence: 99%

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

Arcidiacono

Santhakumari

Viotto

et al. 2018

Adaptive Optics Systems VI

View full text Add to dashboard Cite

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.

show abstract

Section: Discussionmentioning

confidence: 99%

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

Arcidiacono

Santhakumari

Viotto

et al. 2018

Adaptive Optics Systems VI

View full text Add to dashboard Cite

show abstract

Section: Discussionmentioning

confidence: 99%

The measurement of the Interaction Matrices for the LINC-NIRVANA MCAO

Arcidiacono¹,

Bergomi²,

Viotto³

et al. 2017

Proceedings of the Adaptive Optics for Extremely Large Telescopes 5

View full text Add to dashboard Cite

The commissioning of LINC-NIRVANA (LN) is ongoing at the Large Binocular Telescope (LBT). LN provides Multi-Conjugate Adaptive Optics (MCAO) correction for each side of the telescope using the Layer Oriented technique and using Natural Guide Stars (NGS). For each arm, two wavefront sensors (WFS), one conjugated to the ground and the other to 7km, co-add the light of all the reference stars within their respective fields of view, following the Multiple Field-of-View scheme. The two WFS separately control two deformable mirrors (DMs), the 672-actuator adaptive secondary of the LBT (ground layer) and a 349-actuator DM from Xinetics (7km layer). The DMs projections on the WFS cameras rotate, since the opto-mechanics of LN are pupil fixed, while the NGS rotate. We need to provide a distinct control matrix for approximately each degree of rotation. We succeed in obtaining valid control matrices through numerical interpolation of a few calibrated interaction matrices. In this paper, we present the daytime calibration strategy and procedures for LINC-NIRVANA's DM-WFS interaction matrices.

show abstract

“…One of the key activities performed during daytime calibrations concerned the Interaction Matrix (IM) calibration for the LN WFSs. Strategies and lessons-learned from LN Pathfinder experiment [12] were applied. In particular, we note that in order to track off-axis stars during night observations, the wavefront sensors of LINC-NIRVANA, are equipped with a derotator.…”

Section: Day-time and Night-time Commissioning Activitiesmentioning

confidence: 99%

“…In fact, the two arms not only had to match the internal alignment requirements but also they considered the requirement coming from telescope mirrors adjustment capabilities coupled to the uncertainty on the final LN position after its installation on the telescope, which given the size and weight of the overall instrument could only be roughly corrected on-site. Some preliminary hints of the strategy of alignment of the LBT mirrors to the instrument were given by the LN Pathfinder experiment [12] , although the annular field of view of the GWS imposed a further challenge, since the sensor requires an off-axis light source.…”

Section: Alignment To the Telescopementioning

confidence: 99%

Alignment and preliminary outcomes of an ELT-size instrument to a very large telescope: LINC-NIRVANA at LBT

Bergomi¹,

Marafatto²,

Viotto³

et al. 2017

Proceedings of the Adaptive Optics for Extremely Large Telescopes 5

View full text Add to dashboard Cite

LINC-NIRVANA (LN) is a high resolution, near infrared imager that uses a multiple field-of-view, layer-oriented, multiconjugate AO system, consisting of four multi-pyramid wavefront sensors (two for each arm of the Large Binocular Telescope, each conjugated to a different altitude). The system employs up to 40 star probes, looking at up to 20 natural guide stars simultaneously.Its final goal is to perform Fizeau interferometric imaging, thereby achieving ELT-like spatial resolution (22.8 m baseline resolution). For this reason, LN is also equipped with a fringe tracker, a beam combiner and a NIR science camera, for a total of more than 250 optical components and an overall size of approximately 6x4x4.5 meters.This paper describes the tradeoffs evaluated in order to achieve the alignment of the system to the telescope. We note that LN is comparable in size to planned ELT instrumentation. The impact of such alignment strategies will be compared and the selected procedure, where the LBT telescope is, in fact, aligned to the instrument, will be described. Furthermore, results coming from early night-time commissioning of the system will be presented.

show abstract

First light of the LINC-NIRVANA Pathfinder experiment

Cited by 5 publications

References 7 publications

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

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

The measurement of the Interaction Matrices for the LINC-NIRVANA MCAO

Alignment and preliminary outcomes of an ELT-size instrument to a very large telescope: LINC-NIRVANA at LBT

Contact Info

Product

Resources

About