IRCS Basic Instrument Parameters
IRCS consists of two arrays. The "Camera" detector is used for imaging and grism spectroscopy. The detector on the "Spectrograph" side is used when a high-resolution spectrum is obtained with the echelle mode. The imaging mode provides two different pixel scale modes, 20 and 52 mas per pixel (due to the installation of the fiber injection module for IRD, 12 mas pixel-scale mode has been suspended).
| Camera | Spectrograph | |
|---|---|---|
| Detector | both ALADDIN III 10242 InSb array | |
| Pixel size | both 27 μm | |
| Pixel scale | ||
| w/o AO | High (20 mas): 20.42±0.07 mas Low (52 mas): 52.42±0.07 mas |
54.57 x 67.75 mas (slit-length direction x slit-width direction) |
| w AO | High (20 mas): 20.57±0.04 mas Low (52 mas): 52.77±0.04 mas |
54.93 x 68.20 mas (slit-length direction x slit-width direction) |
| Field of view | ||
| w/o AO | High (20 mas): 20.91"2 Low (52 mas): 53.68"2 |
3.5-9.4'' (in slit-length direction) |
| w AO | High (20 mas): 21.06"2 Low (52 mas): 54.04"2 |
3.5-9.4'' (in slit-length direction) |
| Gain | 5.6 e-/ADU | 3.8 e-/ADU |
| Dark current | 0.1 e-/s | 0.05 e-/s |
| Read noise per NDR(1) | 43 e- rms | 68 e- rms |
| Saturation level | 123 000 e- | 129 000 e- |
| Readout rate(2) | both 0.41 s (standard), 0.12 s (fast) |
(1) Readout noise for frame = [Readout noise per NDR] / sqrt(NDR)
(2) For full array size (1K x 1K)
Note: If you need old parameters before July 2005 when IRCS was mounted on Cassegrain focus, please see old parameter page.