2. Instrument parameters

2-1. Integral Field Spectrograph mode

Kyoto3DII Integral field spectrograph (IFS) mode uses a 37 x 37 lenslet array. An image on the focal plane is enlarged by a factor of 34. The lenslet array is rotated by 16.7° with respect to CCD array, along which the micropupils are dispersed.

Table 2-1-1. Observing parameter for IFS mode
telescope Subaru Telescope UH 88 telescope
focus Cassegrain (w/o AO188) Nasmyth (w/ AO188) Cassegrain
pixel scale 0″.096 lens-1 0″.084 lens-1 0″.43 lens-1
field of view 3″.6 3″.1 16″
spectral resolution R ∼ 1200
wavelength coverage 360 - 920 nm† 640 - 920 nm† 360 - 920 nm†
sensitivity‡
[erg s-1 cm-2 Å-1 arcsec-2]		 ~7 x 10-17 at 500 nm
~5 x 10-17 at 660 nm		 ~5 x 10-17 at 660 nm
~5 x 10-17 at 750 nm
~1.2 x 10-16 at 900 nm		 N/A
†Only a part of the wavelength range is observed simultaneously; five (two) wavelength bands cover the whole wavelength range at Cassegrain (Nasmyth) focus.
‡Conditions: 3σ, in 1 lens, in 2 wavelength pixels, 30-minute exposure with present CCD. The estimated total efficiency in IFS mode with present and new CCDs is shown here.

Table 2-1-2. Estimated sensitivity of IFS mode at Nasmyth focus of Subaru Telescope
wavelength
[Å]		 exposure time
[s]		 object flux in the aperture
[erg cm-2 s-1]		 S/N ratio
old CCD new CCD
6600 (No.4) 300 7 x 10-17 3.1 7.9
6600 (No.4) 3600 6 x 10-18 3.0 6.6
7500 (No.5) 300 9 x 10-17 3.0 8.1
7500 (No.5) 3600 8 x 10-18 3.1 7.0
9000 (No.5) 300 2 x 10-16 2.7 14
9000 (No.5) 3600 2 x 10-17 3.1 14
Conditions: The assumed aperture size is 6 x 6 spaxels (= 0.5″ x 0.5″) and 3 wavelength pixels (7.5 Å and 9.9 Å in No.4 and No.5 bands, respectively.) The assumed sky background is 1 x 10-17 erg cm-2 s-1 Å-1 arcsec-2 at all wavelength (dark sky).

2-2. Fabry-Perot mode

Fabry-Perot mode uses an etalon ET-50 made by Queensgate Instruments. An etalon is a pair of reflecting surfaces facing each other, and transmits only the light with the wavelength satisfying the interference condition. Changing the gap between these surfaces, we can change the transparent wavelength arbitrarily. We have two etalons of low and high spectral resolution.

Note: Fabry-Perot observations at the Subaru Nasmyth focus are not available now.

Table 2-2. Observing parameter for Fabry-Perot mode
telescope Subaru Telescope UH 88 telescope
focus Cassegrain (w/o AO188) Nasmyth (w/ AO188) Cassegrain
pixel scale 0″.056 pixel-1 0″.050 pixel-1 0″.25 pixel-1
field of view 1′.9 1′.7 8′.5
spectral resolution R ∼ 400 and 7000
wavelength coverage 400 - 700 nm 640 - 700 nm 400 - 700 nm
sensitivity
[erg s-1 cm-2 arcsec-2]		 ~1.2 x 10-16 at 550 nm (R ~ 200)
~1.3 x 10-16 at 700 nm (R ~ 250)		 N/A N/A
‡Conditions: 3σ, in 1 pixel after 2 x 2 on-chip binning, 30-minute exposure.

2-3. Imaging and longslit-spectrograph modes

Parameters in imaging and longslit-spectrograph modes are the same as those in IFS and Fabry-Perot modes, respectively, because the basic optics, such as the collimater lens and grisms, is common.

Table 2-3. Observing parameters for imaging and longslit-spectrograph modes
telescope Subaru Telescope UH 88 telescope
focus Cassegrain (w/o AO188) Nasmyth (w/ AO188) Cassegrain
pixel scale 0″.056 pixel-1 0″.050 pixel-1 0″.25 pixel-1
field of view (imaging) 1′.9 1′.7 8′.5
slit length 1′.5 1′.3 6′.7
spectral resolution (longslit) R ∼ 1200 for the narrowest slit
wavelength coverage 360 - 920 nm† 640 - 920 nm† 360 - 920 nm†
†Only a part of the wavelength range is observed simultaneously; five (two) wavelength bands cover the whole wavelength range at Cassegrain (Nasmyth) focus.

2-4. Instructions for Kyoto3DII+AO188 observations