A NeXus/HDF5 based file format for STXM

Scanning Transmission X-ray Microscopy (STXM) is a relatively recent and rapidly growing X-ray imaging technique with niche capabilities that are applicable across a wide set of scientific disciplines. Over the years since its invention, technological progress has allowed a much greater volume and wider variety of data to be recorded, while the flexibility of the technique has also given rise to many variations, utilizing different contrast mechanisms, detection modes, scanning modes, sample configurations and sample environments. There is, therefore, increasing dissatisfaction with the predominant data file format. Here, we present a new file format, NXstxm, based on the NeXus standard and utilizing the HDF5 container format. The design of the format is based on principles of 1. All STXM experiments should be possible to describe, 2. The set of common scan types should be easy to read, and 3. Saving of all instrument parameters is encouraged. We further discuss the philosophy behind some of the choices made in defining the NXstxm format.