Development of a Geometry Database and Related Services for the NICA Experiments

This article presents the Geometry Information System (Geometry IS) developed in a configurable manner for use in all the NICA experiments. The general object model and the architecture of the Geometry Database (Geometry DB) are designed and described in detail. The information system contains Central (based on PostgreSQL) and Local (SQLite replica) Geometry Databases. The Central DB is accessible through the Apache Web server and ensures all the functionality for geometry manipulation. The Local Database as part of the ROOT-based frameworks of the NICA experiments is used mostly for loading detector geometries in simulation, reconstruction and physics analysis tasks. Common application programming interfaces and a Web interface are developed. The first one is implemented as a set of user macros with necessary functions, the Web service provides a graphical interface for viewing and editing geometry data of the experiment. A configuration installation system is created for the Geometry IS initialization and deployment. Users of the experiments can immediately start filling the database with the geometry of the detectors via the Web interface after initialization.