12.6 Mosaics and other limitations.

• Mosaics: The pipeline handles mosaics, but with several limitations.
  1. The data has to fit in memory. This is often the case for NOEMA data, but may not be true for ALMA data. Splitting the data in Frequency chunks may be needed.
  2. Self-Calibration is ignored for Mosaics, although there could be cases where sufficient S/N is available for this. There is no inherent impossiblity to do so, since self-calibration behaves in the same way for Single-fields and Mosaics. But this has not been sufficiently tested, and is planned for a future release. Contact us should this need clearly arise.

• Short Spacings The pipeline assumes the available UV tables are complete. They may or may not contain short spacing information. However the pipeline has no specific tool to add short spacings to pure interferometric UV tables. This is up to the user to do so.

• Proper Motion Similarly to short spacings, it is up to the user to correct the UV tables for source proper motions if needed. It should be done on the RAW UV table prior to any further processing. ¹³

• UV table consistency: Also, the PIPELINE is intended for simultaneous observations with a single tuning and single source. Although multiple sources can be handled by using the appropriate file filter, it is recommended to process them in separate sub-directories.

  Non simultaneous observations with different tunings can lead to puzzling inconsistencies. Imagine what might happen if you store data obtained at the same time by two different arrays !...