CFHT Information Bulletin, number 39, Second Semester 1998

KIR: the new IR camera for PUEO

Jean-Luc Beuzit, CFHT Resident Astronomer (

KIR is a 1024 x 1024 near-infrared camera designed to be used at the F/20 focus of PUEO, the CFHT Adaptive Optics Bonnette. KIR is based on the 1K x 1K Rockwell Science Center HAWAII (HgCdTe Astronomical Wide Area Infrared Imaging) focal plane array. This array is sensitive to radiation from 0.7 to 2.5 µm. The camera consists in an LN2 cryostat which harbors the detector, the fixed 0.67:1.0 transfer optics, a F/20 cold stop and a filter wheel. The camera plate scale is 0.035"/pixel, yielding a total field-of-view of 36" x 36". The standard I, J, H, K and K' broad-band filters are provided as well as several narrow-band filters (see below). A preamplifier and a shutter are mounted externally to the dewar. The system is driven by an SDSU/Leach CCD controller which is the system commonly used at CFHT for all visible and infrared detectors. Observers are provided with a user interface, called DetI, incorporated into the CFHT/Pegasus observing environment, through which they will configure the camera, control the data acquisition, monitor the data storage and do some pre-processing. Figure 9 is a picture of KIR on PUEO taken during the July 1998 observing run.

The development of KIR was a collaborative effort between Université de Montréal (René Doyon, Philippe Vallée, Daniel Nadeau), CFHT (Barry Starr, Jean-Charles Cuillandre, Jim Thomas, SueAnn Healey, Jean-Luc Beuzit) and Observatoire Midi-Pyrenées (Francis Beigbeder, Sylvie Brau-Nogué). The cryostat as well as all cryomechanisms and optics were designed and constructed by the Université de Montréal, who also provided the filter wheel controller. Part of the array DSP code was written by the Observatoire Midi-Pyrenées. The acquisition system and software were the responsibility of CFHT.

First light was obtained during the September 1997 technical run and the first astronomical observations were made on December 6th, 1997. Since then KIR has been used successfully on more than 50 nights on PUEO. Figure 10 illustrates recent results obtained with PUEO and KIR.


KIR can hold up to 16 12.7 mm (1/2 inch) filters. The filter cells are deep enough to receive filters that are 6 mm thick. New high optical quality filters have been ordered for KIR. As most of these new filters were not available for semester 98I due to delays in the manufacturing, filters taken from the Redeye Narrow camera were cut down to 1/2 inch and used instead. Starting with semester 98II, the above broad-band and narrow-band filters will be available for general use with KIR (Tables 1 and 2).

For more information and recent upgrades on KIR (filter availability, performances, etc.), please look at our web site ( or contact Jean-Luc Beuzit (

Editor: Dr. Timothy M. C. Abbott,
Copyright © 1998, CFHT Corporation. All rights reserved.