KOOLS-IFU Exposure Time Calculator

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Input

Wavelength
grism
observing wavelength		[Å]
integral range (e.g., spectral resolution)		[Å]

Object Flux
object magnitude (point source)		[AB mag]
object flux in the wavelength range		[erg cm^-2 s^-1]

Sky Condition
seeing (or PSF size)
sky background brightness		[AB mag]
sky background brightness		[erg cm^-2 s^-1 arcsec^-2 Å^-1]

Observation Settings
exposure time of a frame		[sec]
number of frames

For Experts
field of view per fiber		[arcsec²]
optics throughput (including atmosphere and telescope)		[%]
number of combining fibers
object flux fraction in aperture (please change to 100% for extended source)		[%]
number of extract pixels for fiber direction		[pixel]
readout noise		[e^- / pixel]
wavelength-pixel scale		[Å]
M1 radius		[cm]
M1 shaded radius by M2		[cm]

total exp time [sec]	S/N	total signal [e^-]	total noise [e^-]	object photon noise [e^-]	sky photon noise [e^-]	readout noise [e^-]