Find here a quality plot for the co-added products.
We display the full spectral region for a setup. The data are rebinned to 5 A bins and are intended
as overview of the spectral slope, and as indication about the S/N quality of the co-added data.
The overview plot has
- the full co-added spectrum (rebinned to 5 A) on top ('overview');
- a signal/noise plot for the co-added spectrum. It comes in two versions: blue is the S/N as calculated from the spectrum (as displayed on top) and its (pipeline-delivered) errorbar file.
Red dots mark a measurement of S/N over 0.5A bins in which the statistical rms is evaluated. In many
cases stellar absorption lines or telluric lines dominate the fluctuations and hence corrupt
the S/N value. But in favourable cases a spectral region will show pure continuum and give a
realistic estimate of S/N. Hence the upper envelope of the red dots can be seen as a S/N
measurement of the final product spectrum, including all noise sources up to a scale of 0.5A.