The UCLA 24-in Telescope and a Dual Optical-IR Imaging System

A 24-in Cassegrain telescope has been refurbished and equipped with both an infrared camera and a CCD camera. The telescope, which is located in the middle of the UCLA campus in west Los Angeles, is now in regular use for graduate student research, and for undergraduate teaching. A dichroic beamsplitter allows simultaneous imaging observations at optical and IR wavelengths. The CCD camera is a Star I system from Photometries Ltd., modified with a BVRI filter slide, and the IR camera is a simple K-band (2.2 µm) imager developed at UCLA and based on a NICMOS 3 HgCdTe array from Rockwell. The CCD camera has a pixel scale of 0.5 arcsec pixel⁻¹ and the IR camera scale is 0.85 arcsec pixel⁻¹; both have a field of view of about 3 arcmin. Over the past year, much work has been done to align the telescope, characterize the quality of the site, and generally improve the mechanical reliability of the observatory. Seeing is typically 3" in the IR and slightly worse at V. This paper describes the setting up of the telescope and the instruments, and reports sensitivities and airmass corrections for our site. One of the most significant conclusions is that the IR camera enables good work to be done at this very optically bright site. Several highlights of the first year of observing are reported.