Design of the calibration system for LEGEND*

The Large Enriched Germanium Experiment for Neutrinoless Double-beta decay (LEGEND) is an experimental effort to search for neutrinoless double-beta decay in ⁷⁶Ge. Using a phased approach, the collaboration aims to develop an experimental program with the discovery potential reaching a half-life up to 10²⁸ years or longer. In the first 200-kg phase, LEGEND will use existing resources as appropriate to expedite physics results.
In such an ultra-low background experiment, regular calibrations with radioactive standards are necessary to establish the energy response, monitor the stability of the detector performance, and deliver a well-understood data set on which analyses cuts can be developed.

In my talk, I will discuss the challenge of designing a calibration system for such an experiment. I also will present the results of a simulation campaign for LEGEND-200, which outcome is used to address open design questions such as source positioning and activity, expected data rates, and required threshold settings.