Thursday, May 7, 2015

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!