Improved GNIRS back on the Gemini North telescope

GNIRS is back on the Gemini North telescope, following five months of work to replace radioactive camera lenses, add filters, and correct some mechanical unreliability that had become apparent since 2010. We are currently scheduling a mix of science observations (in the popular SBXD+32 l/mm configuration) along with engineering tests that will allow us to open up other modes as soon as possible. The successful lens replacement in the popular “short-blue” camera has resulted in a factor of about 40 decrease in the radiation event rate on the detector. Because of a crack in one of the lenses in the “short-red” camera, and risk of further damage, this camera will not be available until after additional work is completed. This work is planned for mid-2013.