File Formats for XAFS Data

Standardization of file formats for data collected at XAS beamlines is a perenial topic of dicsussion. Although the data from a typical XAS experiment is not especially complicated and is reasonably well represented by a flat, context-free file, it is obviously attractive to incorporate metadata in a structured way into our data files.

There are (at least) two issues that can be addressed in a discussion of file formats. One is the format of a file containing a single scan of data -- i.e. one spectrum to be preocessed and analyzed. A related topic is the storage of data related to the measurement of a scan. For example, a measurement using a multi-channel analyzer might store an entire MCA spectrum at each data point or a microspectroscopy experiment might store a fulle XAS spectrum at each pixel in the map.

The discussion on this page is restricted to the first topic -- the storage with metadata of a single scan of XAS data.

Some time ago, BruceRavel and Ken McIvor from MRCAT, APS Sector 10 drafted a proposal for a single spectrum with metadata file format which would be easy to implement at most extant beamlines, which would be simple to incoporate into most extant data analysis software, and which addresses most of the metadata concerns that Bruce and Ken were able to identify. Here is their draft of the specification (as a PDF file).

Note that the specification calls for the implementation of interface libraries in a variety of common language as part of the development of the standard.

This is related to the discussion on Xafs_Databases