LINC-NIRVANA settles in its new home at LBT

LINC-NIRVANA ready to
leave the clean room 

LINC-NIRVANA (LN) is a near infrared imaging instrument for the Large Binocular Telescope (LBT) designed to offer both multi-conjugate adaptive optics (MCAO) and interferometric beam combination for ultra high spatial resolution. LN is a collaboration between the German and Italian partners. Its Principal Investigator is Tom Herbst (MPIA  - Max Planck Institute for Astronomy, Heidelberg).

The LN bench, without all its opto-mechanical components, was briefly introduced to its new home in November 2015 (see here). 

Following 8 months of assembly, integration, and verification in the mountain clean room, on 19-Sep-2016 the instrument was rolled out of the summit clean room in preparation for the “big lift” planned for the following day. On the morning of 20-Sep-2016 the LBT staff, working in close cooperation with the LN team, carefully flew the 10-ton instrument over the instrument gallery to its designated position at the rear bent Gregorian focal station of LBT. Then on the following day, 21-Sep-2016, the instrument cover and upper instrument access platform (UIAP) were installed. 

On-sky commissioning of the instrument should start in January 2017, following a short glimpse at the sky currently scheduled for late November 2016. 

You will find a few pictures below and videos in the LBTO video gallery.

LN has been carefully moved with the crane to the rear portion of the instrument gallery, as the telescope is gradually raised in elevation to clear the path.  All team members must work in close harmony to achieve this careful choreography.

With the telescope safely locked at the zenith position, LN is lowered the last few meters onto the instrument platform.

A last look at the interior of LINC-NIRVANA before the cover is installed.  

- The two large cylindrical structures with cable chains seen at the front of the instrument (top in this view) are the Ground Layer Wave Front Sensors, one of the first optical systems to receive light from the telescope.  

- The two rectangular black structures at the rear of the instrument (just below the center of the image) are the High Layer Wave Front Sensors. 

- The silver and yellow railing at the bottom center are the rails used to install and remove the cryostat. 

- The surrounding white cabinets contain the computers, networking gear, motor controllers, detector readout electronics, and other services required to operate LN.

Traveling back in time, here is a sketch of LN on the telescope as shown in the first SPIE paper on the instrument (2003).

LINC-NIRVANA is introduced to its new home.

LINC-NIRVANA (LN) is a near infrared imaging instrument for the Large Binocular Telescope (LBT) designed to offer both multi-conjugate adaptive optics (MCAO) and interferometric beam combination for ultra high spatial resolution. LN is a collaboration between the German and Italian partners. Its Principal Investigator is Tom Herbst (MPIA  - Max Planck Institute for Astronomy, Heidelberg).

LN successfully passed its Preliminary Acceptance tests in Heidelberg (Germany) in May 2015. For the following months, the team has been very busy preparing the instrument for shipping, filling up nine 20ft containers and a BIG crate for the LN bench. Before packing the bench itself, a traverse specially built to eventually install the instrument on the LBT was tested in front of the lab at MPIA. It was LN's first flight! (see image on the right)

Bench crate and containers left MPIA in early September and arrived on schedule on Oct 20 and 21 at the MGIO base camp.

Two of the LN containers (left) and the LN bench crate (right) at the MGIO base camp

The bench crate made its way to the mountain on Oct 22, followed by a first set of four containers. They were stored in the high bay, waiting for the arrival of the LN team, eight people from MPIA who started the long reassembly process on Nov 9. The MGIO staff was instrumental in the swift and safe delivery of these heavy loads to the observatory!

Of the many steps in this reassembly process, checking the fit of the LN bench on the telescope is obviously crucial to the whole project. The bench and its traverse were reunited and they both went for a second flight...

Taking off,hanging from the enclosure crane hook 43 meter above the high bay ground.

Reaching the Upper 3 Level where the bogies of the enclosure ride on their track.

Entering the enclosure access well. 

Entering the hatch. The clearance is very small (a fraction of an inch at the narrowest point) 

Nearly done through the narrows...

Finally free to fly in the enclosure!

LN landing pad on the telescope, in front of LBTI (green structure). The two LUCIs (shiny cylinders) are just behind LBTI. The LN bench with its red traverse can be seen through the telescope structure.   

The bench is now as high as possible above the telescope. The telescope has to be lowered to give enough vertical space for the bench to come to the rear of the enclosure before approaching its landing.

Getting closer... 

With the telescope back to zenith, the bench is lowered down toward its platform.

On the telescope!

A video of the whole operation, compiled by T. Herbst, is available on the LBTO video web page.

For a few days (Nov 16-20), the LN bench will stay on the telescope, moving around during night-time as regular observing takes place with the LBTO facility instruments. During day-time, the various platforms and covers, which will eventually be added permanently to support LN operations, will be fit-tested. 

LINC-NIRVANA Lean-MCAO successfully passed its Preliminary Acceptance in Europe

LINC-NIRVANA (LN) is a near infrared imaging instrument for the Large Binocular Telescope (LBT) designed to offer both multi-conjugate adaptive optics (MCAO) and interferometric beam combination for ultra high spatial resolution. LN is a collaboration between the German and Italian partners. Its Principal Investigator is Tom Herbst (MPIA  - Max Planck Institute for Astronomy, Heidelberg).

LINC-NIRVANA in the lab ready for inspection (credit: D. Ashby)

LINC-NIRVANA is a large instrument: roughly 5 x 4 x 4.5 meters and weighing 10 tonnes! There are a total of 40 pyramid wavefront sensors on the optical bench, more than 250 lenses and mirrors, 133 motors, and 966 cables...

LN bench hanging on the stand which simulates the telescope platform  (credit: D. Ashby)

On the picture above, the red structure on the left of the bench replaces (same mass and center of gravity) the ground layer wavefront sensor unit already on the telescope as the PATHFINDER experiment, which allowed to validate on-sky some of the capabilities of the MCAO unit.

The LN team will first deploy LINC-NIRVANA on the telescope in its "Lean-MCAO" configuration: each arm of the instrument will be independently capable to deliver an MCAO corrected 10 arc-second field view. Two MCAO systems on each arm will remove the blurring of the atmosphere coming from its ground layer for one, and its high layers for the other.

"Lean-MCAO" went this week through its Preliminary Acceptance in Europe (PAE) at MPIA. Two days of review and two more for splinter meetings in small groups made for fruitful exchanges between the LN team and seven LBTO staff. The instrument passed the review successfully, with no showstopper and only a few actions to be taken care of!

Happy LINC-NIRVANA team and LBTO reviewers (credit: T. Herbst)

It is now countdown time up to the arrival at the Observatory. Nine 20' containers and a HUGE box housing the bench and its supporting structure will travel by boat from the North Sea shores to California Coast (with a Panama Canal passage on the way). LN will then go on the road and ultimately reach the base camp in November of this year. After a full integration in the mountain lab, the installation of LN on the telescope is currently scheduled for the summer of 2016. The Early Science program in the "Lean-MCAO" configuration should start in 2017, once the commissioning  of the instrument is completed.


Twelve busy years went by since the Preliminary Design Review of the instrument. The success of this PAE is a tribute to those who contributed with much energy and creativity to the project in Germany and Italy.      
 

Congratulations are in order to all involved!

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The LINC-NIRVANA collaboration

• The Max-Planck-Institut für Astronomie, Heidelberg Germany   (MPIA LN Team)
• INAF - Osservatorio Astronomico di Padova, Padova Italy (Padova LN Team)
• INAF - Osservatorio Astronomico di Bologna, Bologna, Italy
• INAF - Osservatorio Astrofisico di Arcetri, Firenze Italy
• Universität zu Köln, Köln Germany   (Köln LN Team)
• The Max-Planck-Institut für Radioastronomie, Bonn Germany   (Bonn LN Team)
• Astronomical Observatory of Rome, Monte Porzio Catone Italy

LUCI2 and Pathfinder see the sky for the first time!

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LUCI2

A few weeks after LUCI2 met LUCI1 on the telescope and quite a few closed-dome (I should write enclosure) tests, it was time for the second of our near infrared imagers and spectrographs to see first light. Six days of commissioning and a reasonable weather made for a very successful run.

Luci2 on its derotator at the front bent focus of the right side of LBT.

LUCI1 (left) and LUCI2 (right) are seen on the instrument platform behind LBTI 

If LUCI2 is mostly a twin of LUCI1, it comes with a brand new software which was checked, improved and optimized in real observing conditions. The usual commissioning observations to characterize the instrument on sky (astrometric and photometric tests in imaging mode, spectrophotometric zero-point determination for grating 200H+K, ...) were carried successfully. As the new software can handle both LUCI2 and LUCI1, an imaging script in binocular mode was sent and correctly executed. All on-sky tasks foreseen for this run have been successfully performed and the basic functionality and performance of the instrument could be demonstrated.

Two more runs scheduled in December and January should conclude the first phase of the LUCI2 commissioning in seeing-limited mode. 

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LINC/NIRVANA Pathfinder

Pathfinder is an effort to bring a substantial portion of the LINC-NIRVANA instrument to the telescope in advance. Specifically, one Ground-Layer Wavefront Sensor (GWS) and its associated drive electronics and software are implemented at the right, rear, bent focus of the LBT. The main goal is to demonstrate ground layer correction of turbulence, as well as establish the needed infrastructure for telescope and adaptive secondary communications. It will also allow the team to perfect the techniques of star acquisition and tracking. 

Working on the instrument at the rear bent focus of the right side of the LBT. The middle focus station is LBTI and the front is LUCI2 (on the right of the picture). 

Three nights following the LUCI2 commissioning run were scheduled for Pathfinder and LBT engineering. Weather has been unfortunately poor, but Pathfinder was lucky enough to have a couple of openings in the clouds sufficient to catch a couple of bright stars! In spite of a 2.3" seeing, loop was closed with 50 Zernike modes on Epsilon Auriga

There is still a long way to go - this was, after all, only a single star on axis. It is however an important step for the whole team, which left Mt Graham very tired, but happy! In coming campaigns, Pathfinder will be operated with multiple stars in ground-layer adaptive optics mode.

More images on the Pathfinder run here.