Requirements

• The pipeline must be able to process all the data coming from the array; it must not constitute in any case a bottle-neck in the data flow.

• The pipeline must operate in fully automated mode for processing from raw data up to deconvolved images. Although this fully automated processing may not lead to optimum quality reduced data, it will constitute the basis for an homogeneous database of processed data.

• The pipeline must also be able to operate in manual mode for technical development, inspections by expert engineers and astronomers on duty but also at the level of the PI/CoI astronomers, for projects which request interactive observations. Requirements (input pipeline parameters) may be given at the stage of the elaboration of the proposals by the astronomers.

• The pipeline must process in quasi real time the observing blocks but, in the imaging stage, it must also be able to include all the observing blocks previously obtained since the project has started. This may mean calibrated data obtained in different antenna configurations.

• The pipeline must interact with various packages, including the Dynamic Scheduler, the actual observing program, various high levels tools for visualization, and the data transmission (compression/decompression, formatting).

• The pipeline must operate through a readable and comprehensive data reduction script. A high level tool may be available to interactively build such a script, but for automated processing it must be automatically generated from a template, on the basis of the scheduler status and of the collected actual observing procedures. For debugging it should also be able to operate at the command line level. Scripts will be composed of basic components such as, pointing, focus, phase calibration, etc... Some of these components will be activated sequentially but other in parallel (in particular at the mapping stage). It must be able to process in parallel sub-arrays.

• The pipeline should be run either at or near the telescope, in quasi real time, or later, at places where the official archives are kept (see Section 7).