TriCCS Exposure Time Calculator

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Input

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

Object Flux
Point source or Extended source with Gaussian profile
object magnitude		[AB mag]
object flux in the wavelength range		[erg cm^-2 s^-1]
seeing (or FWHM of target)

Observation Settings
exposure time of a frame		[sec]
number of frames
CMOS gain (4 for exp_time ≥ 5 sec. 8 for 1 ≤ exp_time ≤ 5 sec.)

Sky Condition
sky background brightness		[AB mag]
sky background brightness		[erg cm^-2 s^-1 arcsec^-2 Å^-1]
Airmass Elevation		1 / cos(90° - Elevation)
Airmass Elevation		[deg]

For Experts
optics throughput (including atmosphere and telescope)		[%] (cf. see throughput@20231017)
object flux fraction in aperture (Gaussian 3-sigma for point source)		[%]
Atmosphere Extinction (extinction curve)		[mag/airmass]
Extinction rate		[%] : Extinction * ( Airmass - 1 )
number of extract pixels		[pixel]
readout noise		[e^- / pixel]
dark current		[e^- s^-1 pixel^-1]
wavelength-pixel scale		[Å]
M1 radius		[cm]
M1 shaded radius by M2		[cm]

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