IRCS Echelle ETC


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Source Type 
Will you use AO188 ?
This AO188 option is useful for only point sources. This calculator assumes FWHM ~ 0."07(JHKLM) and  0."2 (z) after AO-correction. The seeing profile is a Moffat function. See the encircled energy diagram on AO188 webpage.
Observation band
Target magnitude UNIT: mag (for Point sources), mag/arcsec^2 (for Extended sources)
Slit width   arcsecond
S/N required
Seeing   arcsecond
Binning  pixels  Note: The flux of point source spectrum is already summed over  along the slit-length direction in the calculation. You can still binning the spectra along the dispersion direction for the point source. For extended sources, you can binning both along the slit-length and along the dispersion directions. 
Sky Subtraction loss  - 0.376 mag  -2.5 log (sqrt(2))


Programmed by Tae-Soo Pyo 2009.Feb.7

Updated (2011.4.4) by T.S. Pyo