KCWI Characteristics

The following tables list the optical characteristics of KCWI. In some instances (denoted by *) predicted values are listed in lieu of actual measurements.

Table 1: Optical Characteristics

Location Left Nasmyth platform, Keck II; removable from focus
Bandpass (blue channel) 350 to 560 nm
Bandpass (red channel) 560 to 1080 nm
Field of View 20.4 arcsec x (8.4, 16.5, or 33.1) arcsec selectable
Telescope Plate Scale 1.375 arcsec/pixel
Detector Plate Scale 0.15 arcsec/pixel
IFU Pupil Array Radius 225 mm
IFU Slicer Radius 5200 mm
Aberration Correction Cylindrical fold mirror
Slit Height 14.5 mm = 20.4 arcsec
Slit Width 0.25, 0.5, 1 mm = 0.35, 0.69, 1.38 arcsec selectable
Beam Size 150 mm
Collimator Focal Length 2160 mm
Camera Focal Length 305 mm
Gratings VPH, 250 x 350 mm, selectable
Blue Detector e2v 4kx4k, 15 microns pixel, thin, AR-coated CCD
Red Detector LBNL 4kx4k, back-illuminated AR-coated CCD; 15 micron pixels; 500um thick Si substrate; Archon Controller
Image Resolution ~ 10 microns RMS (seeing-limited)
Last modified: 03/13/2025 05:05
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