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40.1.1 Standard Header Packet
The Standard Header Packet (SHP) contains the instrument engineering telemetry values, and other data from spacecraft operations. The telemetry values found in the SHP are observed values and may include quantities that are not controllable.40.1.2 Unique Data Log
The Unique Data Log contains commanded values for various instrument settings. The UDL also contains data from the flight software.40.1.3 Science Data Files
Science data are stored as single-precision floating point values. The results of the pipeline calibration are files containing the HSP count rates as a function of time. The number of files in the dataset depends on the mode and the data type. A single observation could generate up to eight separate data files. Science data files are identified by their suffixes as shown in Table 40.2.
40.1.4 Quality Mask Files
Each of the science data files has a corresponding quality file that contains single-precision floating point values. Good data values are identified in the file with a value of zero. An error at any pixel during the data capture process results in a non-zero value. HSP data quality flag values are listed in Table 40.3.
Flag Value |
Description |
---|---|
0
|
Good data
|
1
|
Reed-Solomon decoding error
|
8
|
A/D converter saturation
|
16
|
Missing data
|
40.1.5 Calibrated Data Files
The HSP calibration program, calhsp, generates the calibrated file for each corresponding raw science data file. The calibrated and the raw data header files contain the same keywords, except the raw data are corrected for instrument signatures.
Note that the photometric sensitivity is poorly determined and the calibration correspondingly uncertain.
40.1.6 HSP Data Products
Generally, most HSP data are delivered from the Archive in FITS format. For large volume data samples, FITS format files may not be produced. In this case the delivered data remain in GEIS format. 40.1.7 HSP Keywords
Table 40.4 describes important HSP keywords. This table does not include all keywords that are found in all of the data headers.