Myriad advances in Gemini ’ s instrumentation and capabilities occurred in 2016 . This review looks at these developments and what the future holds for Gemini ’ s instrumentation program .
January 2017
Gemini staff contributions
On the Horizon
Myriad advances in Gemini ’ s instrumentation and capabilities occurred in 2016 . This review looks at these developments and what the future holds for Gemini ’ s instrumentation program .
January 2017
GeMS ’ Next Generation Natural Guide Star Sensor : Making Progress
GeMS , the Multi-conjugate adaptive optics System deployed at Gemini-South , has been in use for several years now , producing spectacular results with its capability to deliver diffraction-limited image quality over a field more than 1 arcminute wide . To achieve this performance GeMS uses five laser guide stars for high-order wavefront sensing , and up to three natural guide stars ( NGS ) for tip-tilt and plate scale modes sensing . However , operation of GeMS is rather complex , principally due to technical issues . Recent technological developments have opened the possibility to improve the operational efficiency drastically ( for instance , see page 47 of this issue to read about the new laser system being procured ). Here we report on developments to enhance the selection and performance of natural guide star tip-tilt sensing .
A key problem encountered in GeMS operation revolves around the acquisition of natural guide stars . The existing Natural Guide Star Wavefront Sensor ( NGS WFS ) used for tip-tilt sensing suffers from low throughput , which severely reduces the number of stars that can be acquired , thereby diminishing the amount of sky coverage attainable by GeMS . Furthermore , the existing NGS WFS system uses three mechanical pickup probes , each of which can patrol the whole field . But these probes have only a very small field-of-view which , due to flexure and variable field distortions , sometimes makes it time consuming to acquire the stars .
Thanks to current state-of-the-art detector technology that has become available , these limitations can now be tackled . A key change is that rather than having three mechani-
January 2017 | 2016 Year in Review GeminiFocus
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