KOOLS-IFU Exposure Time Calculator

KOOLS-IFU Exposure Time Calculator

This ETC was updated on 2020/Mar./25. Please recalculate the results obtained before.

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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]
[erg cm-2 s-1 arcsec-2 Å-1]
Observation Settings
exposure time of a frame [sec]
number of frames
image rotator In Out
For Experts
field of view per fiber [arcsec2]
optics throughput [%]
number of combining fibers
throughput due to fiber filling factor [%]
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]

†: including the fiber core filling factor at the 2D array (58%)


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