Review of Gemini South Laser Guide Star Facility performance and upgrades

The Gemini South (GS) Observatory acquired a 50W sodium Guide Star Laser System in March 2010, as one of the key components of the Gemini Multi-Conjugate Adaptive Optics System (GeMS) project. After a successful post-delivery acceptance in laboratory, the system was installed on the elevation platform of the telescope. Following an intensive period of optimization, the Gemini South Laser Guide Star Facility (LGSF) delivered its first light on the sky in January 2011 [1]. Over the two years following the event, and while the LGSF was being commissioned, the GS LGSF team was able to gather substantial data concerning its laser and laser launch system, which allowed to improve both their overall performance and reliability. This work is critical, taking into account that the LGSF system will go from development to normal operations mode in March 2013. This paper will report on the LGSF performance during GeMS runs over two years of use. It will then provide an exhaustive list of the numerous findings made over this period, and will explain what has been done to enhance the system.