Characterization of Signal and Background Detectors for Dark Matter Search

The DArk Messenger Searches at an Accelerator (DAMSA) experiment is designed to search for dark sector particles decaying to electromagnetic final states at a beam dump facility. A sensitive search requires not only a high-performance detector but also a thorough understanding of neutron backgrounds. This presentation will cover the research and development for two detector systems for DAMSA: a CsI-based electromagnetic calorimeter and a borated organic liquid scintillator-based neutron detector.

The poster will first present the characterization of prototype modules for the DAMSA electromagnetic calorimeter, which uses Cesium Iodide (CsI) crystals coupled to SiPMs. We will discuss the calibration of these detectors, including measurements of their light yield and energy resolution, which are crucial for reconstructing the signatures of potential dark sector particles.

In addition, the poster will also discuss the development of a neutron detector designed to measure neutron backgrounds for the DAMSA beam dump target. We will present the analysis techniques used to distinguish neutron signals from gamma backgrounds, to accurately quantify and mitigate neutron-induced background fluctuations.