Gemini Observatory took responsibility for FLAMINGOS-2 in 2009. Several issues were identified during testing need to be addressed before FLAMINGOS-2 can enter science operations. The Observatory had the resources and expertise, including engineers and machinists, to do this work. A detailed analysis of the remaining effort estimated that F2 will be ready to be re-commissioned at the end of 2011 and during early 2012. The schedule change was largely a consequence of significant redesign that has been necessary in some critical areas. Key elements of the plan to improve FLAMINGOS-2 are listed here and the periodic updatesposted in the recent milestones section.

Detector: The science detector, a Gemini-furnished Hawaii-2, needs to be replaced. The tentative delivery date for at least one new detector is in 2010. Gemini might purchase an additional detector depending on the availability of a better one. Background: since 2008, a small but growing number of dead pixels have appeared in the lower right corner of the detector. Once the detector arrived at Cerro Pachón, 30% of the upper right quadrant was found to be unusable, so the current detector is no longer acceptable for regular science use. This first image obtained with F2 shows the extent of the unresponsive pixels.

Thermal stability: Work is planned to improve the thermal and vacuum stability of the camera and MOS dewars. The MOS dewar cooling time must also be reduced to allow for K-band observations the same night of a daytime mask change.

Mechanism reliability: The MOS wheel drive mechanism is essential for all spectral observations, including longslit mode. On the basis of experience during the initial commissioning, Gemini changed the design for more robust long-term operations. The decker wheel, window cover, and gate valve baffle also required improvements before going into long-term operations.

R~3000 grism: The University of Florida is procuring a replacement of the higher-resolution grism.

Documentation: The University of Florida will provide complete documentation, including as-built drawings, which are required to keep the planned servicing on schedule.

Recent milestones:

• January 2012. FLAMINGOS-2 received its "second first light" on the Gemini South telescope in early December 2011. The instrument is performing very well and commissioning is progressing. At the end of December a mask change was performed while the camera dewar was closed and the first test MOS spectra were obtained in early January. The OIWFS is in the process of being commissioned. A decision regarding System Verification will be made by mid-January 2012.

• October 2011. A new and improved FLAMINGOS-2 returned to Cerro Pachon on October 3rd, 2011. The instrument was re-integrated without problem and began cooling on October 27th. The myriad improvements of the last 18 months are readily apparent in the high quality of the vacuum achieved in both cryostats and the improved thermal control and performance of the cryostats and, more importantly, the science detector. Warm and cold mechanism tests also showed much improved mechanical performance, particularly of the MOS wheel and the gate valve. The new Hawaii-2 science detector is healthy, detailed characterization is under way. On November 8th, the instrument was installed on the flexure rig in the CP instrument lab to undergo extensive flexure and reliability tests. Everything is currently on track for the long-awaited return of F-2 to the Gemini South telescope on November 23rd, 2011.

• August 2011. We have had a lot of work and have made a lot of good progress. We have performed flexure and repeatability testing with the instrument cold. Its performance has been good and only minor fixes have been planned. These fixes will not stop us from sending the instrument to Cerro Pachon before the end of the year. Moreover, we have installed the new science grade detector and started characterizing it.

• June 2011. We have started checking the performance of the assembled F2 instrument in the lab. The next step is to perform a full optical alignment and one more cold test of the instrument. After this, we would install the science grade detector and prepare for work in the flex rig. This is a more detailed list of the work completed so far:
  • Tested all mechanisms with the instrument cold.
  • Fixed some problems with the detector focus stage
  • Improved the design of the current gate valve baffle such that it can work at any orientation
  • Tested the new thermal control setup with a bare MUX and an engineering grade detector.
  • Checked for basic flexure of the mechanisms
• April 2011. Most of the mechanical upgrades and fixes have been completed. These include outstanding issues like installing a redesigned gate valve baffle moving mechanism. Other completed work
  • Initial design for a new thermal control setup for the Hawaii 2 detector.
  • Mapping of the detent positions for the MOS wheel.
  • Design and implementation of a new controller for the cold foot mechanism used in the MOS dewar.
  • Final testing of the mask making software (GMMPS) for F2.

• March 2011. We have made progress on several fronts:
  • We cold tested succesfully the new MOS wheel mechanism.
  • We have checked the thermal and vacuum stability of the MOS dewar. We are starting to test the camera dewar.
  • The UF has delivered a new R3K grism and installed it on F2.
  • The UF staff also extracted the O-ring from the lens barrel and realigned it
  • We received a new Hawaii-2 detector at Gemini-South.
• October 2010. The new Hawaii-2 detector has been shipped from Teledyne. It will arrive to Gemini South in November.

• August 2010. Progress was made on the following:
  • Evaluating the current camera lens barrel.
  • Assessing the IQ impact of the current lens barrel assembly.
  • Assembling new MOS mechanism parts.
  • Fixing software issues related to the image headers, OIWFS control, and misc.
  • Testing of the iraf reduction package .

• July 2010. We opened the camera dewar and performed a through inspection of it in early July. Several issues were identified:
  • Spilled Activated carbon from a loose getter.
  • Loose lens radial defining pins
  • Anodized vacuum seals
  • Loose limit actuators in the gate valve baffle mechanism
  • O-ring present in the cryogenic lens barrel.

• June 2010. The laboratory was prepared for opening the camera dewar. Final designs for other MOS mechanisms are being completed. We are also working on finalizing outstanding software issues in collaboration with the University of Florida team. Moreover, Florida has received the parts for the R3K grism that we hope we will install later this year.

• May 2010. A new version for GMMPS, the Gemini mask making package, was developed. This version will support the design of F2 masks. New parts for the MOS wheel gear mechanism are being fabricated. Preparations for opening and inspecting the camera dewar are underway.

• April 2010. Full revision of the MOS dewar has been completed. We have identified several ways to minimize the problems found with the MOS dewar mechanisms. A new design for the MOS wheel gear train has been proposed.

• March 2010. F2 was transported from the summit to SBF Instrument Lab. N. Raines from University of Florida will be visiting Gemini South to help out with the work. Initial work will be concentrated on the MOS wheel mechanism.

• February 2010. F2 was taken off the telescope and preparations started for transport to La Serena. A new instrument lab has been prepared to receive F2 at SBF where its upgrade will take place. F2 is expected to be in La Serena by the end of March.

• January 2010: imaging and long-slit commissioning run. Testing was limited due to malfunctioning of the MOS wheel.

• November 2009: on-sky acceptance tests completed. Identified several critical issues to be addressed, described above.

• September 2009: on-sky acceptance tests and first light. The OIWFS was not used due to a critical misalignment of the mechanism.

• August 2009: FLAMINGOS-2 arrived at Cerro Pachón

• May 2009: third pre-ship acceptance test. The instrument was approved for shipping to Chile. However, some waivers were issued (gate valve baffle operating in the up-looking port, time-to-function for the MOS wheel) and some issues were deferred in order to speed up the shipping process (testing of the MOS dewar cool-down time and available documentation such as as-built drawings and final manuals).

• December 2008: second pre-ship acceptance test. Several mechanisms failed to work reliably and it was agreed that a third AT would be necessary.

• August 2008: first pre-ship acceptance test. A coldhead failure prevented full testing.

• February 2006: FLAMINGOS-2 website goes online.