The GIRAFFE calibration scheme is rather simple. A complete set of calibrations
consist of three or more flats and one arclamp calibration per setup,
and a set of bias frames.
The bias frames are processed by the pipeline in an 'elementary' way,
without other calibration products involved. The flats are processed next,
with a master bias required as input, and with the fibre localization,
width, and extraction products. The arc-lamp frame is processed into the
dispersion solution table, using the master bias, and the localization
and width products. It also has a product called ARC_RBNSPECTRA which
is the extracted and rebinned arc-lamp spectrum for all fibres. This product
is useful for quality assessment. All products from the flat recipe, and
the dispersion solution from the wave recipe, are required to process
science frames. There is also a set of static tables, the slit_geometry_setup
tables and the grating table, which are required tocompletely describe
the wavelength calibration solution.
Presently, the Argus standard star data are also processed like a science
frame, in order to give a starting point for a flux calibration of the
Argus science data.
In quick-look mode on Paranal, the Giraffe pipeline has a fixed set of
calibration products which are all static. Hence these dependencies cannot
be properly respected. The calibration solutions processed by QC Garching
do respect the cascade. Together with quality checking, this results in
the optimum possible products, meaning that any instrumental and ambient
influence on the science data is monitored and removed by the calibration
products in the best possible way.
Find the GIRAFFE calibration cascade here. Click on "sub-cascades" to explore MEDUSA, IFU or ARGUS sub-cascades, or on "ALL" to see the whole cascade.