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Standard Data Processing Release Notes

All data received from the Chandra X-ray Observatory is processed through the standard data processing pipelines at the Chandra X-ray Center. The pipelines are updated regularly to fix bugs, add new capabilities and enhance existing capabilities, and to respond to changes in the way the observatory is operated. To assist users in understanding how these changes may alter the standard data products, or to identify whether there are enhancements or bug fixes in new software releases that are relevant to specific data products or areas of scientific interest, the following release notes are provided. The version of the standard data processing system used to produce any data product is identified in the FITS headers by the ASCDSVER keyword.

These release notes address revisions to the standard data processing pipelines that may affect data products available to observers. They do not include information on updates to the CIAO data analysis system, changes that affect only non-end user data products (for example, spacecraft monitoring and trending analysis pipelines), or that are related only to the internal software infrastructure and do not alter any data products.

These release notes also do not address changes to data products that occur because of revisions to the calibration data used in the processing (after the Chandra calibration database (CALDB) became available for use in standard data processing). Changes to the calibration data are described in the CALDB release notes. The version of the CALDB used to produce any data product is identified in the FITS header by the CALDBVER keyword.

Current release notes

CXC data system software releases 6.0.0 and later:

Earlier release notes are also available for data system software releases prior to 6.0.0 as far back as release R4CU5UPD7:

Last modified: 25 March 2003

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