Over the past several months, improvements and upgrades have continued on a wide range of projects and telescopes at CTIO. As John Filhaber mentions in a separate article, the 4-m image improvement program remains at high priority, and the last several months have seen gratifyingly better image quality. The reliability of the Shack-Hartmann system has been increased, and the active primary support system is working well. Tests of the guiding and servo system have been started, and work to enhance their performance to realize fully the image quality now delivered by the telescope optics is scheduled for the engineering shutdown in July and August (see the article by Steve Heathcote). The mounting system for the f/14 secondary has been installed and tests of various components of the system have begun as part of our f/14 tip-tilt project. In particular, a high speed version of the CTIO CCDTV guide camera is being developed as the sensor. The f/14 mirror is being finished in Tucson, and is scheduled to be installed in mid-June. Tests of the tip-tilt system will begin next semester, with a goal of having a usable system by the end of the calendar year.
As was mentioned in the last Newsletter, the NOAO Cryogenic Optical Bench (COB) will be moving to CTIO in the second semester, and the CTIO IRS is being upgraded to work with the new f/14 secondary. On a longer time scale the NOAO Mosaic and the Hydra/CTIO instruments (see separate articles) are scheduled for initial deployment on the Blanco Telescope in 1998.
During March, Dave Mills from KPNO visited for three weeks and worked intensively with German Schumacher on the new 4-m GUI project. This GUI is derived from the one in use on the WIYN telescope, and from the user perspective, is similar to that at the KPNO Mayall telescope. A fully working prototype is now in nightly use on the Blanco, and offers improved guide star acquisition and more efficient telescope operation. The final version will be installed during the engineering shutdown. Documentation for users will be made available at that point.
The efforts of our Arcon development team have concentrated on preparing the controllers for the NOAO Mosaic instrument. Many of the team members will travel to Tucson during May and June to integrate the CCDs and software for the first engineering tests on the 0.9-m. During the course of this development, the performance of the base system has been enhanced to allow more rapid readout of the CCDs. Systems currently in use on Tololo have benefited from these more rapid readouts.
At the Schmidt, the long awaited NFCCD mounting box, shutter/filterbolt and smart motor controller were integrated and installed. The Schmidt now joins the 4-m in having fully automated focus from the Arcon user-interface, thus increasing observing efficiency and lessening the caloric expenditure from the rapid run up the stairs to change filters and refocus. (The dome is still not encoded, so observers do need to go upstairs to check and move it).
With considerable expert help from Rob Seaman of KPNO, the Save-the-Bits (STB) software has been installed at the 0.9-m and Schmidt telescopes. STB, a completely automatic data archiver, has been in operation at KPNO for over two years (see previous Newsletter). After each CCD readout, data is saved on exabyte tape. At the time of writing (April) the system is still being debugged, but it is expected to be fully operational soon. It will then be installed on the other telescopes, and for use with the Wildfire IR detector, during engineering runs over the coming months.
A dome ventilation system for the 1.5-m has been designed and is being fabricated in our La Serena shop. An array of 32 doors with a total area of over 500 square feet in area will be installed in the dome segments around the lower rim of the dome. We plan to begin installation of these doors next semester, which should improve the thermal environment of this dome.
Bob Schommer Chair, ACTR