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2 | Quality plots
Same region in:
SpT = B:
HD_79469 (B9.5V, Z=0.4)
Other SpT:
O || A F G K M Unknown Telluric
UVES NGSL Project: HD_79469
1 Overview   2 Quality plots   3 Detailed spectra   [download tar]
BLU_346   BLU_437   REDL_580   REDU_580   REDL_860   REDU_860  
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.