Quality Control and
Data Processing

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 for the wavelength calibration solution.

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. These master calibrations are archived and can be downloaded using the calSelector service.

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.