6.2. Quality Control

The Quality Control Report is a product to gather, combine and distribute information on the quality of the observation science data. Quality Control includes, per observation, the assessment of the execution of the observation by the spacecraft and the instruments, the evaluation of the success of the data processing, the outcome of the systematic inspection of the Quick Look product and, if required, the instrument specialist and community support astronomer analysis. The Quality Control Summary Report is an extract of the Quality Control Report which compiles the final relevant and pertinent quality information for the users.

The Quality Control Report is automatically created during the Data processing for each observation. The Quality Control Report Summary is generated at the end of the quality control analysis as a result of this process.

Herschel Quality Control Summary Report

Figure 6.1. Herschel Quality Control Summary Report


Besides the attributes and the common metadata of other Herschel products, the Quality Control Reports also contains the following fields:

6.2.1. Quality Flags

The first set of Quality flags populating the Quality Control Report are derived from the auxiliary products which contain the Spacecraft and Instruments information reported by the MOC.

  • Missing Telemetry: The observation is fully or partially affected by an interruption of the telemetry.

  • Out of Limits: One or more parameters are out of the allowed value.

  • Event:During the observation the MOC reported a kind of event from either the instrument or the spacecraft.

  • Telecommand Errors:This flag reports error coming from the Telecommand History product.

  • High glitch rate:The observation suffered an anomalously high glitch rate.

  • Pointing Problem / Suspicious Pointing: Pointing problem means that the actual pointing was significantly off the target, or the target was not acquired at all. Suspicious pointing is applied when the pointing may not be accurate and/or the object may not be well centered.

A generic flag "S/W Problem at processing level" is raised when the Data processing system fails at any step during the processing of the observation and a number of products are missing.

The last set of flags are generated by the instrument specific pipelines.

The list of flags which are transferred from the Quality Control Report to the Quality Control Summary Report after the quality analysis as useful information for the users are listed in Appendix B.