Workflow information system for QC

This plot shows the mean signal-to-noise ratio of XSHOOTER tellurics as a function of the mean counts. Tellurics are telluric standard stars processed like science files as IDPs. They should ideally show, like the classical IDPs, a square-root law (indicated by the dotted lines which are NOT fits). Since their spectral characteristics are more uniform than for the IDPs, their correlation curves are expected to show less scatter.

For the UVB and VIS arm we display correlations for the two detector gain values offered (low gain = lg or high gain = hg) and the two mostly used binnings (1x1 binning or 2x2). We display the same reference slit widths as for the classical IDPs. The NOD values in plot #1 are for datancom=2 only.

Within each box we use different colors for the 2 observing techniques used for tellurics:

• red for STARE (single exposure),
• green for NODDING (exposure pairs, or multiple pairs).

We have added data points for all modes and slits for a given read mode and binning as small black points. We have also added (for the two upper, well-populated boxes) square-root laws for orientation. Note that they apply to the date range after 2013-01 only, due to a major pipeline change in that month. For the earlier data another normalization factor applies to the flat-field that is reflected in a different scale for the mean_counts parameter (X-axis). These relations are also plotted in the FULL plot (only), marked by that date.

In the NIR-arm, the left box is for the STARE mode observations including the mapping template observations which are processed by the STARE pipeline recipe. The right box displays the NODDING data, broken down by the reference slit width and the most frequently used values of N (PRO.DATANCOM, the total number of combined raw frames).