XMM-NEWTON ARCHIVE
The XMM-Newton Archive consists of the data products for the individual observations, as well as various derived catalogues, such as the XMM Serendipitous Source catalogue. Both kinds of data are accessible through on-line interfaces maintained by ESA at the XMM SOC, as well as by NASA at the XMM GOF / HEASARC.
A separate database maintained by ESA allows you to track observation planning, execution, and data production for accepted targets.
Observation data is subject to a proprietary period for (usually) one year after data delivery to the PI. Proprietary observation data for US based PIs (only) are available (in a PGP encoded format) at the GOF, along with all publically available observation data.
In addition to the raw observation data the archives contain a number of pipeline data products produced for each observation. The version of the software, and associated calibration files, used for the pipeline production may not be the most recent version, though the bulk of the archive has been reprocessed through at least SAS version 7.1 (completed during the summer of 2007). Later observations generally use the most current version of the SAS at the time of the data delivery.
XMM Science Archive (XSA)
The SOC maintained XSA info page contains links to FAQs, manual, guides, etc., as well as the links for the various source catalogues as ASCII downloads. The XSA facility itself is a java applet wrapper around the SOC database. A simple example on using it is here. When you request data via the XSA you can simultaneously request that a subset of the pipeline products be reprocessed using current versions of the SAS and calibration.GOF Mirror Archive (Browse)
The GOF maintained XMM-Newton observation data archive is accessed through the HEASARC Browse facility. The Browse facility also is able to access the various XMM catalogues. Reprocessing of the pipeline products must be done by the requester (See the XMM GOF Data Analysis page). Using the XMM tools in the Hera facility easily guarentees using the most up to date software and calibration files.At present the Optical Monitor source catalogue (OMCat) is currently produced at the GOF, and is accessed in Browse as the xmmomobj catalogue. This will be supplanted by a catalogue produced at MSSL and maintained by the SOC at some point.
If you have any questions concerning XMM-Newton send e-mail to xmmhelp@lists.nasa.gov