In high-energy physics (HEP), conditions databases play a critical role in managing non-event data. This includes calibration constants, alignment parameters, and detector conditions, which evolve over time. These databases ensure that analysis software can access the correct calibration and alignment data corresponding to the detector’s state at any given time, enabling accurate physics measurements.
The HEP Software Foundation (HSF) proposes a Conditions Database reference for HEP and Nuclear Physics experiments around the world. Several experts have converged on a common design for conditions data access management arXiv:1901.05429. The nopayloaddb is an implementation of this reference. It has been successfully operating within the sPHENIX experiment for nearly two years and is currently being adopted by Belle II. Additionally, other collaborations, including ePIC and the Einstein Telescope, have expressed interest in evaluating its suitability for their needs.