Plot
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Symb
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Source
* |
Average ? |
Thresholds ? |
N_
data |
QC1
parameter |
Data
downloads |
Remarks |
| method |
value |
unit |
method |
value |
| 1 |
o | QC1DB |
none |
|
ADU |
none | |
0 |
mean_signal |
this |
last_yr |
all
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new CCD (after 2008-04): mean image flat value in ADU, as function of exposure time |
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*Data sources: QC1DB: QC1 database; LOCAL: local text file
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| Plot 1 | | data source: | giraffe_ccd
(QC1 database) |
| dataset: | mean_signal | o |
| average: | none |
| thresholds: | none |
| N_data plotted: | 0 |
| [click on plot for closeup] |
| average: | none |
| thresholds: | none |
| [click on plot for closeup] |
| average: | none |
| thresholds: | none |
| [click on plot for closeup] |
This report hosts correlation plots for the monitoring of the GIRAFFE
linearity and gain, derived from image flats. These data are taken
about monthly. Since 2008-07, they are acquired with the
common detector monitoring template and reduced with the corresponding common
recipe.
Note the CCD upgrade between 2008-03 and 2008-05. Plots #3 and 4 are available
for the new CCD only.
A sequence of image flats is exposed
between 0.5 and 220 secs. Their average exposure level is plotted against the
exposure time (box 1). The fitted function corresponds to
mean = 245*exptime for the old CCD, and 195*exptime for the new CCD. In box 3,
non-linear residuals are plotted vs. exposure time (new CCD only).
PLot 4 (for the new CCD only) shows the GAIN values plotted over exposure
time. The asymptotic value for texp -> 0 is the true GAIN. The value stored in
the file headers is indicated as "nominal".
Find the trending of non-linearity coefficient and gain here.
General information
Click on any of the plots to see a close-up version.
The latest date is indicated on top of the plot, data points belonging to that date are specially marked.
If configured,
- statistical averages are indicated by a solid line, and thresholds by broken lines
- outliers are marked by a red asterisk. They are defined as data points outside the
threshold lines
- "aliens" (= data points outside the plot Y limits) are marked by a red arrow (↑ or ↓)
- you can download the data for each parameter set if the 'Data downloads' link shows up
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