The following EPIC PN Science Files are defined:
These are all binary table files. All except type 6 are used in the standard data analysis. The content of types 1-4 will be described below.
Type 5 (Offset Data Image) files contain the offset maps taken on board at the start of each exposure. The offset maps contain the per pixel energy offsets for each active CCD of the configured mode; during the exposure, these offsets are subtracted on board from the measured signals.
Type 6 (Noise Data Image) files are used for diagnostic purposes and are not required for standard data analysis. They contain the per pixel offset variance.
Type 7 (Discarded Lines Image) files are present in those cases where cosmic rays have hit a PN CCDs. They contain information on the number of lines blanked as a result of a detected cosmic ray interaction.
Type 8 (Counting Cycle Report) auxiliary files provide a summary record of the data lost when the telemetry rate is exceeded by the data rate produced by the PN cameras (i.e., when the PN is operated in so-called Counting Mode).
Types 7 and 8 are required in the standard data reduction for a proper exposure correction.
As for the other XMM-Newton instruments, the PN ODF files do not explicitly contain a column TIME. PN imaging, timing and burst modes contain a "Frame Counter", that increments monotonically in steps of 1 for the full detector. The ODF/SDF contain no time information in UT units, this has to be calculated using the time correlation file.
It is important to note that the above modes do not map one-to-one with the instrument modes defined in . In particular:
The above files can be recognised by the value of the keyword DATATYPE in their binary table header, as indicated in Table 3.