Sensitivity Estimate for SPICA/SMI/HRS (DRS)
-array size; 1K×1K Si:As BIB detector
-dark current; 0.2 electron/pix
-read noise; 25.0 electrons per readout
-saturation full well; 2.0E+5 (electrons)
-pixel pitch; 18 (µm/pix)
-exposure time; 600 (sec)
-shortest exposure time; 2 (sec)
-detector qunatum efficiency; "DETQE_SIAS.DAT" (electron/photon)
【optics】
-diameter of the primary mirror; 2.5m
-secondary mirror shielding rate; 0.2
-plate scale; 0.67 (arcsec/pix)
-slit width; 1.7 (arcsec)
-energy fraction within 1st null radius; 0.9
-system efficiency (incl. lens and filters, etc); 0.3
-relative grating efficiency (echelle grating and cross disperser); "SMI-HRS_GEFF.DAT"
Data Format:
1st column; Echelle order
2nd column; wavelength (µm)
3rd column; relative grating efficiency; ηechelle(λ) x ηcross disperser(λ)
-peak efficiency (ηechelle(λ) x ηcross disperser(λ)); 0.4
【others】
-high background case;
・zodiacal light emission at ecliptic plane (β=0.0deg and ε=60deg)
・black body of T=268.5 K normalizzed to 80 MJy/sr at 25µm
-low background case;
・zodiacal light emission at ecliptic pole (β=90.0deg)
・black body of T=274.0 K normalizzed to 15 MJy/sr at 25µm
(Reach et al. 2003; Ootsubo et al. 2000)
- safety factor; 0.8
- number of pixels used to extract spectrum along cross dispersion direction;
first null diameter of the airy disk
(calculated for the adopted spectral resolution of R=λ/Δλairy)
ASKII Data:
"1H5S_SENSITIVITY_HRS_mJy_R_DRS.DAT"
Data Format:
1st column; wavelength (µm)
2nd column; 1-hour 5-sigma continuum sensitivity for a point source (mJy) [low background case]
3rd column; 1-hour 5-sigma continuum sensitivity for a point source (mJy) [high background case]
ASKII Data:
"1H5S_LINE_SENSITIVITY_HRS_Wm-2_DRS.DAT"
Data Format:
1st column; wavelength (µm)
2nd column; 1-hour 5-sigma line sensitivity for a point source (W/m2) [low background case]
3rd column; 1-hour 5-sigma line sensitivity for a point source (W/m2) [high background case]
(calculated for the adopted spectral resolution of R=λ/Δλslit)
ASKII Data:
"1H5S_SENSITIVITY_HRS_MJY-SR_R_DRS.DAT"
Data Format:
1st column; wavelength (µm)
2nd column; 1-hour 5-sigma continuum sensitivity for extended sources (MJy/sr) [low background case]
3rd column; 1-hour 5-sigma continuum sensitivity for extended sources (MJy/sr) [high background case]
ASKII Data:
"1H5S_LINE_SENSITIVITY_HRS_Wm-2-SR_DRS.DAT"
Data Format:
1st column; wavelength (µm)
2nd column; 1-hour 5-sigma line sensitivity for extended sources (W/m2/sr) [low background case]
3rd column; 1-hour 5-sigma line sensitivity for extended sources (W/m2/sr) [high background case]
ASKII Data:
"SATURATION_HRS_JY_DRS.DAT"
Data Format:
1st column; wavelength (µm)
2nd column; saturation limit for a point source (Jy) [low background case]
3rd column; saturation limit for a point source (Jy) [high background case]
version 2016.10.26 (Itsuki Sakon) [contact: isakon@astron.s.u-tokyo.ac.jp]
1. Assumptions
【detectors】-array size; 1K×1K Si:As BIB detector
-dark current; 0.2 electron/pix
-read noise; 25.0 electrons per readout
-saturation full well; 2.0E+5 (electrons)
-pixel pitch; 18 (µm/pix)
-exposure time; 600 (sec)
-shortest exposure time; 2 (sec)
-detector qunatum efficiency; "DETQE_SIAS.DAT" (electron/photon)
【optics】
-diameter of the primary mirror; 2.5m
-secondary mirror shielding rate; 0.2
-plate scale; 0.67 (arcsec/pix)
-slit width; 1.7 (arcsec)
-energy fraction within 1st null radius; 0.9
-system efficiency (incl. lens and filters, etc); 0.3
-relative grating efficiency (echelle grating and cross disperser); "SMI-HRS_GEFF.DAT"
Data Format:
1st column; Echelle order
2nd column; wavelength (µm)
3rd column; relative grating efficiency; ηechelle(λ) x ηcross disperser(λ)
-peak efficiency (ηechelle(λ) x ηcross disperser(λ)); 0.4
【others】
-high background case;
・zodiacal light emission at ecliptic plane (β=0.0deg and ε=60deg)
・black body of T=268.5 K normalizzed to 80 MJy/sr at 25µm
-low background case;
・zodiacal light emission at ecliptic pole (β=90.0deg)
・black body of T=274.0 K normalizzed to 15 MJy/sr at 25µm
(Reach et al. 2003; Ootsubo et al. 2000)
- safety factor; 0.8
- number of pixels used to extract spectrum along cross dispersion direction;
first null diameter of the airy disk
2. Estimated Sensitivity
2.1. 1-hour 5-sigma continuum sensitivity for a point source
(calculated for the adopted spectral resolution of R=λ/Δλairy)
ASKII Data:
"1H5S_SENSITIVITY_HRS_mJy_R_DRS.DAT"
Data Format:
1st column; wavelength (µm)
2nd column; 1-hour 5-sigma continuum sensitivity for a point source (mJy) [low background case]
3rd column; 1-hour 5-sigma continuum sensitivity for a point source (mJy) [high background case]
2.2. 1-hour 5-sigma line sensitivity for a point source
ASKII Data:
"1H5S_LINE_SENSITIVITY_HRS_Wm-2_DRS.DAT"
Data Format:
1st column; wavelength (µm)
2nd column; 1-hour 5-sigma line sensitivity for a point source (W/m2) [low background case]
3rd column; 1-hour 5-sigma line sensitivity for a point source (W/m2) [high background case]
2.3. 1-hour 5-sigma continuum sensitivity for extended sources
(calculated for the adopted spectral resolution of R=λ/Δλslit)
ASKII Data:
"1H5S_SENSITIVITY_HRS_MJY-SR_R_DRS.DAT"
Data Format:
1st column; wavelength (µm)
2nd column; 1-hour 5-sigma continuum sensitivity for extended sources (MJy/sr) [low background case]
3rd column; 1-hour 5-sigma continuum sensitivity for extended sources (MJy/sr) [high background case]
2.4. 1-hour 5-sigma line sensitivity for extended sources
ASKII Data:
"1H5S_LINE_SENSITIVITY_HRS_Wm-2-SR_DRS.DAT"
Data Format:
1st column; wavelength (µm)
2nd column; 1-hour 5-sigma line sensitivity for extended sources (W/m2/sr) [low background case]
3rd column; 1-hour 5-sigma line sensitivity for extended sources (W/m2/sr) [high background case]
2.5. Saturation limit for a point source
ASKII Data:
"SATURATION_HRS_JY_DRS.DAT"
Data Format:
1st column; wavelength (µm)
2nd column; saturation limit for a point source (Jy) [low background case]
3rd column; saturation limit for a point source (Jy) [high background case]