Documenting experiments: ELN and Metadata schemata on the example of TAS

DAPHNE4NFDI is a consortium within the Nationale Forschungsdaten Infrastuktur (NFDI) in Germany dedicated to developing data management tools and best practices for research data from Photon and Neutron (PaN) sources. The consortium's tasks include collecting and documenting data and metadata during experiments to develop data's FAIRness (Findability, Accessibility, Interoperability, and Reuse). To illustrate this initiative, we focus on inelastic X-ray and neutron scattering (INS/IXS), which are remarkable techniques for investigating the dynamics of condensed matter. Such experiments, however, are only possible at large-scale facilities like nuclear reactors and synchrotrons. The limited number of these facilities, coupled with their significant operational costs, fosters intense competition among researchers eager to gather valuable data, thus elevating the worth of the datasets produced. Therefore, the significance of detailed documentation describing these data sets cannot be overstated. Each dataset requires a robust set of metadata to facilitate future (re-)analyses. Our goal in this endeavor is to establish suitable metadata vocabularies for INS/IXS techniques and to advance the use of electronic laboratory notebooks (ELN), streamlining and enhancing the documentation of our experiments. Here we focus on the triple-axis neutron spectrometer (TAS) as our demonstration use case. At its core, this instrument serves users by producing data that can easily be organized in an ASCII file. Yet, the flexibility of a TAS and its wide range of applications still yield a complex set of metadata. The challenge intensifies when comparing data files collected from various TAS instruments at different facilities. To face this problem, we formulated the draft recommendations for the captured, aggregated, and stored metadata of experiments at PaN large-scale infrastructure facilities [1], which are published and can be used by the community. In particular, we proposed a comprehensive metadata set applicable to most TAS experiments [1]. In parallel, we formulated the essential requirements for an electronic laboratory notebook tailored for the neutron and X-ray community [2]. These results guide the selection of the appropriate ELN software for a facility/institute/instrument. Being a neutron spectroscopy group at the Heinz Maier-Leibnitz Zentrum (MLZ), we are dedicated to advancing the electronic laboratory notebook (ELN) system, designed to support MLZ users in documenting their experiments efficiently and effortlessly. The MLZ-ELN is currently under development to be used as an ELN solution at the MLZ. The aim is to seamlessly integrate the ELN into the local instrument and software infrastructure, facilitating user access control, direct input from the instrument control system, as well as an intuitive user interface. To summarize, here we present draft recommendations for the captured, aggregated, and stored metadata of experiments at PaN large-scale infrastructure facilities, as well as an electronic lab book that we are developing and setting up for the MLZ.