ESPRESSO: Spectroscopic flat fields
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HC PLOTS |
Flat fields |
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QC1 database (advanced users):
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Spectroscopic flat fields are used for determining the order profiles and the
blaze functions per order. There are typically ten frames per input
fibre (A or B). They are measured daily in HR with 1x1 and 2x1 binning;
flat fields for UHR and MR are normally taken only when
UHR or MR science data have been observed during the night.
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Spectroscopic flat-field frame. Example raw frame for the blue detector. The apparent gaps in the orders come from the pre-/overscan of the read-out ports.
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Signal-to-noise ratio
QC1_parameters
FITS key |
QC1 database: table, name |
definition |
class* |
HC_plot** |
more docu |
none | espresso_flat..fiba_snr_min | minimum SNR of all orders for fibre A | CAL | | [docuSys coming] |
none | espresso_flat..fibb_snr_min | minimum SNR of all orders for fibre B | CAL | | [docuSys coming] |
*Class: KPI - instrument performance; HC - instrument health; CAL - calibration quality; ENG - engineering parameter
**There might be more than one. |
Trending
The minimum signal-to-noise ratio per order is trended separately for fibres A and B
and for the five different combinations of resolving power and binning:
HR with 1x1 and 2x1 binning, UHR with 1x1 binning, and MR with 4x2 and 8x4
binning.
Scoring&thresholds Signal-to-noise ratio
Thresholds have not yet been defined.
History
No particular events.
Algorithm Signal-to-noise ratio
The pipeline calculates the signal-to-noise ratio for each order. The QC
procedure determines from these values the minimum per fibre.
Counts and saturation check
QC1_parameters
FITS key |
QC1 database: table, name |
definition |
class* |
HC_plot** |
more docu |
QC.EXT0.ROXm.ROYn.MAX.FLUX | espresso_flat..fiba_counts_max_blue | maximum number of counts for fibre A on blue detector [e-] | CAL | | [docuSys coming] |
QC.EXT1.ROXm.ROYn.MAX.FLUX | espresso_flat..fiba_counts_max_red | maximum number of counts for fibre A on red detector [e-] | CAL | | [docuSys coming] |
QC.EXT0.ROXm.ROYn.MAX.FLUX | espresso_flat..fibb_counts_max_blue | maximum number of counts for fibre B on blue detector [e-] | CAL | | [docuSys coming] |
QC.EXT1.ROXm.ROYn.MAX.FLUX | espresso_flat..fibb_counts_max_red | maximum number of counts for fibre B on red detector [e-] | CAL | | [docuSys coming] |
*Class: KPI - instrument performance; HC - instrument health; CAL - calibration quality; ENG - engineering parameter
**There might be more than one. |
Trending
The maximum number of counts is trended separately for fibres A and B,
for both detectors,
and for the five different combinations of resolving power and binning:
HR with 1x1 and 2x1 binning, UHR with 1x1 binning, and MR with 4x2 and 8x4
binning.
Scoring&thresholds Counts and saturation check
The upper limit has been set to 60000 ADU which is slightly below the
saturation limit of 65535 ADU. The lower limit is at 20000 ADU which
represents the accepted range in early operations.
History
Data taken before October 2010 have been processed with a pipeline version
that converted ADUs into electrons (with about 1.1 e-/ADU).
Algorithm Counts and saturation check
Pipeline calculated values per read-out port. The QC script uses these
values to determine the maximum for each of the chips.
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