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NOEMA pipeline and AoD notes

In the project account, the reports directory contains the first calibration results produced or revised by the AoD (Sect. [*]). The gzipped postscript and ascii files report on the calibration. Particularly those whose names include -pipe result from the automatic data reduction or pipeline (Sect. [*]). You will get familiar with the calibration reports in Sects. [*], [*] and [*]. The AoD performing the observations evaluates the data quality and calibration, and may write notes in the ascii file of extension note. It is recommended to read the notes relative to each track before starting its calibration. The files of extension hpb, so-called header files, store the parameters derived from the calibration.

Having a look at the automatic reports before starting the calibration may be useful, mainly for an experimented astronomer. They can be used, for instance, to decide on the first track to calibrate, likely the one with the best flux calibration. In addition, note that the AoD at Bure performs a comprehensive analysis of the observations, and his/her notes (in the note file) may be useful to identify problems, which perhaps are visible in some of the plots of the First Look report (see Sect. [*] and App. [*]). Recommendations concerning the calibration might also be added to the AoD notes.

Nowadays the pipeline is distributed with every release of GILDAS, although it can only be used with data obtained later than January 2007. You just need to type ``@pipeline `project_name' `date' '' and the pipeline will be launched, producing outputs very similar to those obtained at the observatory. It has become usual among NOEMA users to start the data calibration by launching the pipeline. If this first calibration is not satisfactory, the analysis of the pipeline report, with the help of the AoD notes and the local contact, allow improving easily the data calibration. Anyway, we recommend to have a critical look at the pipeline output protocols before making use of the hpb files. Particularly, it is known that the Data Quality Assessment procedure launched at the end of the calibration often flags out more data than actually needed. If you plan to recalibrate all or parts of the calibration from the pipeline-produced hpb file, we recommend first to remove all the Data Quality Assessment flags by using the following commands:

file both `file_name.hpb'
store flag redu /ant all /reset
store flag redu /base all /reset

At the end of the new calibration you can use the Data Quality Assessment procedure (Sect. [*]) to flag the undesirable data according to the needs of your project.

next up previous contents
Next: How the data look Up: Data Calibration with CLIC Previous: Data Calibration with CLIC   Contents
Gildas manager 2018-12-15