Change page style: 

Sensitivity and Overheads

You are here

It is recommended that the user consult the Sensitivity Table or the Sensitivity Plots to estimate limiting magnitudes and total integration times.

The Phoenix Integration Time Calculator (ITC) can be used to obtain a rough estimate of limiting magnitudes and integration times required to achieve a specified signal-to-noise ratio, for a wide range of source properties and Phoenix configurations. However, the Phoenix ITC assumes that the earth's atmosphere is perfectly transparent. Thus, if specific wavelengths of interest coincide with strong telluric absorption lines or strong OH emission lines, the sensitivities values in the table will be optimistic (possibly greatly so).

Investigators should inform themselves of the atmospheric spectrum by consulting the provided high resolution atmospheric transmission spectrum and, after determining the transmission at their precise wavelengths of interest, modify their estimated integration times accordingly from the values given in the tables.