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- The sensitivity tables assume photometric conditions (50%-ile cloud cover), grey time (80%-ile sky background) and an airmass of less than 1.2. Note however that the OH sky emission can vary by a factor of ~2 up or down during the night
- Individual exposure times of 600s were assumed for all cases.
- Observations are assumed to be at f/32 and dithered (target object in the field at all times); sky subtraction noise is included.
The values in these tables are based on results from the NIRI Integration Time Calculator. They assume 70-percentile (IQ70, ~average) image quality for all categories, photometric conditions (CC50), and an airmass of less than 1.2 for the sensitivites presented here.
The values below are based on measurements at the telescope. These values are similar to what is estimated by the T-ReCS Integration Time Calculator. The overall accuracy of the ITC S/N values is of the order of a factor of 1.2 to 1.4, since conditions at the telescope may vary during an observation, and since for faint targets the assumed square-root of time scaling will not hold exactly. For faint targets we advise people to be conservative in their exposure times to ensure that the desired S/N is obtained. Sensitivity estimates are available for
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