The new CFHT-IR camera is based on the 1K x 1K Rockwell Science Center HAWAII (HgCdTe Astronomical Wide Area Infrared Imaging) focal plane array and includes a cryostat with two 8-position filter wheels and a pupil mask. The excellent optical and throughput performances of the instrument promise to greatly enhance the near-infrared imaging and spectroscopic capabilities of CFHT. The same pixel scale of 0.211''/pixel is used for both direct imaging and multi-object spectroscopy, leading to a total field-of-view of 3.6' x 3.6' on the sky. The main characteristics of the CFHT-IR camera are summarized in the table below.
|Detector format||1024 x 1024|
|Spectral range||0.85 - 2.40 µm|
|Plate scale||0.211 +/- 0.001''/pixel|
|Pixel size||18.5 µm / pixel|
|Total field of view||3.6' x 3.6'|
|Operating temperature||77 K|
|Dark current||0.02 e-/sec|
|Full well capacity||45 000 ADU/110.000 e-|
|Linearity (1%)||35 000 ADU/80.000 e-|
|Mean quantum efficiency (detector only)||
|Minimum integration time||0.1 sec (with shutter); 1 sec (in staring mode)|
|Maximum integration time||1 hour (not recommanded)|
|Readout time (full frame)||1 second|
The following pictures were taken during the preliminary integration of the cryostat at CFHT or at Universitée de Montréeal.
CFHT selected Rockwell HAWAII array number #142 as the science grade array for CFHT-IR in April 2000. This array has a mean QE of 76% for 99.5% of the array. The mean dark current is 0.04 e-/sec.
Here is a dark map and here is a flat field as received from Rockwell.
CFHT-IR is driven by a second generation San Diego State University (SDSU) CCD controller, which has been selected as the new controller for visible and infrared detectors at CFHT (CFH12K, EEV, etc.), and a 4-channel pre-amplifier mounted on the dewar. The total detector readout and delivery time is 1 second.
The observing sessions provides the observer with a user interface
identical to the CFH12K one, called DetCom, incorporated into the CFHT/Pegasus
observing environment, through which they configure the camera,
control the data acquisition, monitor the data storage and do some
pre-processing. Commands can be issued either from a GUI form or at the
command line level, the latter feature allowing relatively complex
sequences of observations, such as dithering and mosaics, to be prepared in
advance using C-shell scripts.
The CFHT-IR filters have been integrated into the CFHT Interference Filter Database and their detailed characteristics can be retrieved here.
Please note that for the imaging mode, all CFHT-IR filters are identical
to the corresponding KIR ones. For the spectroscopic mode, the 3 filters
previously available with Redeye on OSIS are still used.