The First Light of the Subaru Laser Guide Star Adaptive Optics System

The overview and the first light result of the laser guide star adaptive optics (AO188) system for Subaru Telescope is presented. It is installed at the IR Nasmyth platform of Subaru 8 m telescope, whereas the current AO system with 36 elements is operating at the Cassegrain focus. The new AO system has a 188 element wavefront curvature sensor with photon counting APD modules and 188 element bimorph mirror. It has a 4.5 W solid state sum-frequency laser on the Nasmyth platform. The laser launching telescope with 50 cm aperture is installed at behind the secondary mirror. The laser beam is transferred to the laser launching telescope using photonic crystal single mode fiber cable. The instrument with the AO system is IRCS, infrared camera and spectrograph which has been used for Cassegrain AO system and new instrument, HiCIAO, high dynamic range infrared camera for exoplanet detection. We had the first closed loop on sky in October 2006 and projected laser to the sky at the same observing run. 1