<title>Performance and results with a double-beam infrared camera</title>

Abstract

This paper describes the performance of a unique new IR array camera system which provides simultaneous imaging at two wavelengths in the near IR. Two-color imaging is achieved with a dichroic beam splitter which yields two independent beams, one short-wave (SW) from 1 to 2.5 micrometers and one long-wave (LW) from 2 to 5 micrometers . A Rockwell NICMOS 3 256 by 256 HgCdTe array is used in the SW channel and the LW channel has an InSb 256 by 256 array from SBRC. The instrument, which is designed for the University of California's Lick Observatory 3-m telescope and for the f/15 focus of the 10-m W.M. Keck telescope, employs a closed cycle refrigerator and a compact array control/data acquisition system based on transputers with a host 486 PC. On the Lick 3-m telescope the pixel size is 0.7' which gives a field of view of about 180' by 180'. Facilities are also provided for spectroscopy and polarimetry. Recent observational results are reported to illustrate the performance of this system.