Laser guide star upgrade of Altair at Gemini North

Maxime Boccas, François Rigaut, Matthieu Bec, Benjamin Irarrazaval, E. James, Angelic Ebbers, Céline d’Orgeville, Kenny Grace, Gustavo Arriagada, Stan Karewicz,

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2006 · 38 citations · 0 references

Concepts

Abstract

Altair is the general-purpose Adaptive Optics bench installed on Gemini North that has operated successfully with Natural Guide Star (NGS) since 2003. The original design and fabrication included an additional WaveFront Sensor (WFS) to enable operation with Laser Guide Star (LGS). Altair has been recently upgraded and functional commissioning was performed between June and November 2005. The insertion of a dichroic beamsplitter in the NGS path allows to reflect the 589nm light to the LGS wavefront sensor and transmit the visible light of the NGS (or Tip-Tilt Guide star -TTGS-) to the tip-tilt-focus sensors. We will review the various modifications made for this dual operation, both in hardware and software, and describe the steps and results of the integration and testing phase on the sky.