The ITC includes adjustments for observing conditions in its calculations. The meanings of the observing condition criteria are explained in detail in the Observing Conditions ITC help pages. We also assumed an airmass of less than 1.2 for the sensitivites presented here. The estimates below are for long exposures that are background-limited in all cases As a result, there is practically no difference in achieved sensitivities between the different cameras. The facility Adaptive Optics system Altair will not be available during the first year of NIRI operation.
Observations are assumed to be dithered and sky subtraction noise is included.
All individual exposures include the source. The sensitivity values in the table below use the optimum ITC aperture. For uniform surface brightness sources, an aperture with an area of 1 square arcsec is used.