Health Check monitor

Plot 1 scores: 2|
data source:	giraffe_flat (QC1 database)
dataset: (numbers below apply to this dataset)	qc_numsat	•
average:	none
fixed thresholds:	0...1000	number
N_data plotted:	68
[click plot for closeup]

Plot 2 scores: 3|
data source:	giraffe_flat (QC1 database)
dataset: (numbers below apply to this dataset)	qc_numsat	+
average:	none
fixed thresholds:	0...1000	number
N_data plotted:	59
[click plot for closeup]

Plot 4 scores: 2|
data source:	giraffe_flat (QC1 database)
dataset: (numbers below apply to this dataset)	qc_numsat	∗
average:	none
fixed thresholds:	0...1000	number
N_data plotted:	20
[click plot for closeup]

Plot 5 scores: 2|
data source:	giraffe_flat (QC1 database)
dataset: (numbers below apply to this dataset)	qc_numsat	▲
average:	none
fixed thresholds:	0...1000	number
N_data plotted:	17
[click plot for closeup]

Plot 6 scores: 1|
data source:	giraffe_flat (QC1 database)
dataset: (numbers below apply to this dataset)	qc_numsat	•
average:	none
fixed thresholds:	0...1000	number
N_data plotted:	27
[click plot for closeup]

This is the Health Check plot for checking saturation of GIRAFFE flat field calibration data. A saturated flat field can still be used for localization of the fibre signal (unless in extreme cases), but the information related to pixel-to-pixel gain variations, to fringing and to fibre-to-fibre sensitivity is lost in the saturated regions. Therefore all measured flats are monitored in terms of saturated pixels.

We display the QC1 parameter qc_numsat (QC.NUMSAT) which registers the number of pixels close or at saturation (> 60,000 ADU). The alert level is set to 1000 ADU which is more or less arbitrary but experience shows that data with higher values indeed have an issue.

This plot monitors all flat field data. The HC flats (L543.1) are displayed in colour.

The values are usually 0, a flat with saturation stands out clearly. The upper threshold is more or less arbitrary, it is used to get an alert.