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Source Type Point Source Extended Source

Will you use AO188 ? Yes No
This AO188 option is useful for only point sources with 0."5 seeing condition. This calculator assumes the half-flux radius (~ FWHM) of the target becomes about 0."07(JHKLM), 0."2 (z) after AO-correction. The seeing profile is a Moffat function. See the encircled energy diagram on AO188 webpage.

Observation band zJ J H K L M

Target magnitude
UNIT: mag (for Point sources), mag/arcsec^2 (for Extended sources)

S/N required

Seeing (arcsec) 0.3 0.4 0.5 0.7 1.0

Binning along the slit-length direction (pixels)
Binning parameter is for only extended sources. We assume that a point source spectrum is already summed the pixels over 1 or 2 times seeing FWHM area along the slit-length direction.

Slit width (arcsec) 0.14 for R=20,000 0.27 for R=10,000 0.54 for R=5,000