Organization of Data: SciCat metadata catalog

SciCat is an open source, modern and flexible metadata catalog that allows the management of research data supporting the FAIR principles. This metadata catalog was initially developed for the Photon and Neutron (PaN) communities at Paul Scherrer Institut (PSI) and European Spallation Source (ESS) and later supported by European projects PANOSC (The Photon and Neutron Open Science Cluster) and ExPaNDS (The European Open Science Cloud Photon and Neutron Data Service). The community driven development SciCat is increasingly adopted throughout the European PaN communities, and it is recommended by DAPHNE4NFDI. Among the PaN large scale facilities that are either in the process of integrating SciCat into their research data management or have it already in production are Deutsches Elektronen-Synchrotron DESY, MLZ, PSI, Max IV, and ESS. The rapid growth of SciCat has been made possible by its flexibility. Within the DAPHNE4NFDI projects, the use of SciCat is also explored for academic research groups that are not embedded into the supporting infrastructure of the PaN large scale facilities. A modern metadata catalog like SciCat can collect, filter, format and organize all information needed and from different sources. This is especially important for PaN user facilities, that are providers of research data. In order to strive for adherence of the FAIR principles, the metadata catalog needs to contain information, among others, on experimenters, used techniques, samples under investigation. The flexibility of SciCat facilitates an adequate metadata annotation for a wide range of instrumental techniques and scientific topics, as typically occurring in user operation of these facilities. While SciCat is an community driven project, the integration into the facility infrastructure at the Heinz Maier-Leibnitz Zentrum (MLZ) is currently being developed. First and foremost, this includes technical tools to automatically ingest both administrative (such as the principle investigator and the used instrument) as well as scientific metadata (such as the sample or the relevant environment parameters) into the metadata catalogue at the time of data collection. This is achieved via a loose coupling between the instrument control system Nicos (Networked Instrument Control System) that acts as a metadata aggregator and the SciCat catalogue via a dedicated message broker system based on RabitMQ and the corresponding ingestors are being developed. At MLZ , all these systems are running on Kubernetes clusters to make the maintenance and handling manageable. In spring 2025, the demonstrator for the entire data chain (covering the user management software, instrument control and experiment conduction to the creation of datasets and subsequent automatic ingestion into the SciCat catalog has been presented at the DAPHNE4NFDIannual meeting. Once in production, SciCat will serve the users of MLZ to organize and access their research data, with authentication and access control governed by the data policy of MLZ. This work was supported by the consortium DAPHNE4NFDI in the context of the work of the NFDI e.V. The consortium is funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) - project number 460248799.