NOAO expects to make the 1.3-m telescope on Kitt Peak available to a new operating group sometime in the next few months. While the details of the process of awarding the telescope to a new group must be worked out with the NSF, it is likely that formal proposals will be required and that these proposals will be reviewed and evaluated by an external committee of referees. The goal of this Newsletter article is to describe the telescope in sufficient detail that interested groups can begin thinking about the nature of the proposal that they will submit.
The criteria for evaluating proposals to operate the 1.3-m remain to be determined but are likely to include the science programs to be pursued with the telescope; the plans for refurbishing it and placing it into service; the plans for instrumentation; whether or not any time or data (from, e.g. planned surveys) would be made publicly available; the experience of the proposing group; and the soundness of the plan for funding refurbishment and operations. In principle, we are open to a variety of options for continued operation of the 1.3-m, including operation in place, transfer to a new site, and "leasing" the telescope for a fixed period of time for a specific scientific purpose.
The telescope itself has a 1.3-m primary and f/13.5 and f/15 foci and has traditionally been used primarily for infrared and optical photometry. The low-background f/15 chopping secondary is slightly undersized, filling 123 cm of the 127 cm nominal primary diameter. Chopping to 300" off axis is possible, and the approximate plate scale is 11.34"/mm. The conventional fixed secondary at f/13.5 offers a plate scale of 11.7"/mm and a field-of-view of 20'.
The primary and secondary baffles are easily removed for low-emissivity IR work. A reflective cone in the center of the secondary eliminates radiation from the central hole in the primary. The image quality is not well established, but the best reported image quality with the chopping secondary is 1.4" and with the fixed secondary is 1.1". These numbers are upper bounds because no record of seeing is available, and the telescope was normally used with pixels too large to sample the point spread function properly.
The maximum load capacity of the telescope is 200 kgm at a center-of-gravity 52 cm from the mounting surface at the back of the telescope.
No instrumentation or computers will be supplied with the telescope. All spares, equipment, and ancillaries specific to the telescope itself will be made available (e.g. alignment fixtures, spare electronics for the chopping secondary, etc.)
The current telescope control system is the KPNO FORTH-based system running on a DEC PDP 11/44 computer. It was in working condition when the telescope was last used (February 1996), but we recommend that the TCS be replaced with a system based on off-the-shelf components.
The pointing performance depends slightly on telescope loading. The most recent measurements yielded RMS pointing in both RA and Dec of 13" (for 18 stars and hour angles up to three hours and declinations from + 60° to - 30°) with a maximum error of 24" and a minimum error of 5". The telescope is equipped with both incremental and absolute encoders. The absolute encoders are sufficiently coarse that the finder telescope must be used to acquire the first star of the night when the power has been turned off. Telescope settling time after a slew is 1-3 seconds.
People interested in additional information, such as approximate operating costs on Kitt Peak and drawings of the optical configuration and bolt pattern for Cassegrain instruments should contact the undersigned. The formal announcement of opportunity will be made later this year via this Newsletter, the NOAO Web distribution list, and the AAS Newsletter.
Sidney C. Wolff