Plot 4 scores: 9|
data source:	uves_fmtchk (QC1 database)
dataset:	mean_dx	+
median:	-4.185	[pix]
rel. thresholds:	-6.185...-2.185	[pix]
N_data plotted:	106
[click on plot for closeup]

Plot 5 scores: 9|
data source:	uves_fmtchk (QC1 database)
dataset:	mean_dy	+
median:	5.306	[pix]
rel. thresholds:	3.806...6.806	[pix]
N_data plotted:	106
[click on plot for closeup]

Plot 6 scores: 9|
data source:	uves_fmtchk (QC1 database)
dataset:	nlin_sel	+
mean:	318.00943	NONE
fixed thresholds:	300.0...500.0	NONE
N_data plotted:	106
[click on plot for closeup]

This is the trending report for UVES QC parameters derived from the Echelle format check calibrations taken in wavelength setting 860nm, RED Upper CCD. The results are redundant with the "860L" plot except for plot #6 which monitors the number of lines and therefore also the pipeline recipe quality.

Calibrating SCIENCE observations made during the night with calibrations taken during the day relies on the stability and reproducibility of the positioning of the instrument components. To ensure an accurate wavelength calibration, one of the critical criteria is the accuracy of the positioning of the gratings. If the highest possible accuracy is required for the wavelength calibration, an attached wavelength calibration should be taken with the science. Alternatively, since the exact grating position can not be measured in the science image itself, we rely on the daily health check format check data to verify the stability and reproducibility from day to day, assuming that this is a reasonable indication of the reproducibility between nighttime science and daytime calibrations.

With this in mind the important aspects in these plots are the day to day scatter. The absolute level, within reason (i.e. plus or minus 10 pixels) is not important.

From time to time there are sudden jumps in the mean levels, sometimes due to earthquakes, but often the cause of the jump is far from obvious. Such jumps are not in themselves a cause for immediate concern. Only if they are happening frequently, and liable to be happening during the night. Or if they take the instrument so far from the Physical Model that the pipeline will have serious difficulties to converge to a solution, as a rule of thumb, intervention to realign should be considered if the residuals exceed plus or minus 10 pixels.

The individual plots describe:

1. average air temperature of the camera [C] (INS.TEMP4.NAME). Trends in the residuals often correlate with temperature.
2. same as 1
3. same as 1
4. the mean residual in X of the fitted position of the emission lines with respect to the positions expected from the Physical Model
5. the same in Y
6. the number of emission lines selected in the final solution. Trends in this parameter can be due to lamp aging effects

Find more information about UVES Grating Position monitoring here.