The Laser Guide Star facility ARGOS will provide Ground Layer Adaptive Optics to the Large Binocular
Telescope (LBT). The system operates three pulsed laser beacons above each of the two primary mirrors, which
are Rayleigh scattered in 12km height. This enables correction over a wide field of view, using the adaptive
secondary mirror of the LBT. The ARGOS laser system is designed around commercially available, pulsed
Nd:YAG lasers working at 532 nm. In preparation for a successful commissioning, it is important to ascertain
that the specifications are met for every component of the laser system. The testing of assembled, optical
subsystems is likewise necessary. In particular it is required to confirm a high output power, beam quality and
pulse stability of the beacons. In a second step, the integrated laser system along with its electronic cabinets
are installed on a telescope simulator. This unit is capable of carrying the whole assembly and can be tilted
to imitate working conditions at the LBT. It allows alignment and functionality testing of the entire system,
ensuring that flexure compensation and system diagnosis work properly in different orientations.
ARGOS the Advanced Rayleigh guided Ground layer adaptive Optics System for the LBT (Large Binocular Telescope)
is built by a German-Italian-American consortium. It will be a seeing reducer correcting the turbulence in the lower
atmosphere over a field of 2' radius. In such way we expect to improve the spatial resolution over the seeing of about a
factor of two and more and to increase the throughput for spectroscopy accordingly. In its initial implementation,
ARGOS will feed the two near-infrared spectrograph and imager - LUCI I and LUCI II.
The system consist of six Rayleigh lasers - three per eye of the LBT. The lasers are launched from the back of the
adaptive secondary mirror of the LBT. ARGOS has one wavefront sensor unit per primary mirror of the LBT, each of the
units with three Shack-Hartmann sensors, which are imaged on one detector.
In 2010 and 2011, we already mounted parts of the instrument at the telescope to provide an environment for the main
sub-systems. The commissioning of the instrument will start in 2012 in a staged approach. We will give an overview of
ARGOS and its goals and report about the status and new challenges we encountered during the building phase. Finally
we will give an outlook of the upcoming work, how we will operate it and further possibilities the system enables by