GeminiFocus April 2016 | Page 16

Contributions by Gemini staff News for Users With the start of Semester 2016A, we are recovering from a difficult 2015B at Gemini South. We put that bad semester in context here by describing the way the queue responds to difficult weather and instrumentation circumstances. Also in the south, reductions in GPI’s vibrational signature have resulted in a much better raw wavefront and a better vibrational environment for the other instruments. We have also begun the process of replacing the GeMS laser. Elsewhere, the new Gemini Observatory Archive is off to a good start, and we give some early usage statistics. Finally, we look back at Australia’s key contributions during its Partnership with Gemini, which ended in December 2015. How the Queue Responds to Adversity All observatories attempt to complete science programs against a variety of competing factors: weather, equipment failures, earthquakes, etc. Queue scheduling attempts to preferentially complete programs blessed with the highest science ranking by the Time Allocation Committees (TACs), whatever the competing factors put in the way. Weather losses, commissionings, earthquakes, and other events in recent years have given us quite a roller-coaster ride, and it’s interesting to see how queue scheduling (recently the largest part of the Gemini science program) has responded to these challenges. Here we look at an exceptional semester (one with good conditions and more science time than originally planned) and a bad semester (affected by weather and technical problems) and summarize the results. 14 GeminiFocus April 2016