XLUM: an open data format for the exchange and long-term preservation of luminescence data.

Luminescence-dating studies produce vast bodies of primary data that usually remain inaccessible or incompatible with future studies or adjacent scientific disciplines. To facilitate open data exchange and long-term data preservation in luminescence dating studies, we propose a new XML-based structured data format called XLUM [1]. The design applies a hierarchical data storage concept consisting of a root node (node 0), a sample (node 1), a sequence (node 2), a record (node 3) and a curve (node 4). The curve level holds information on the technical component (e.g., photomultiplier, thermocouple). A finite number of curves represent a record (e.g., an optically stimulated luminescence curve). Records are part of a sequence measured for a particular sample. Our format proposal allows the user to retain information from the measurement process on a technical component level. The additional storage of related metadata fosters future data mining projects on large datasets. The XML-based format is less memory efficient than binary formats; however, in focus is data exchange, preservation and hence XLUM long-term format stability. XLUM is inherently stable to future updates and backwards compatible. We support XLUM through two new software packages for R and Python, each called 'xlum' [2, 3]. Both packages facilitate the import of XLUM files into the respective environment. The R package 'xlum' converts existing luminescence-data file formats (e.g., *.bin/binx, *.psl, *.xsyg) into the new XLUM format. XLUM is licensed under the MIT license and hence available for free to be used in open and closed-source commercial and non-commercial software and research projects. Our presentation will outline the basic concept of XLUM, discuss advantages and disadvantages and sketch possible future format progress. [ABSTRACT FROM AUTHOR]