Tea in the Atrium Room: 307

Colloquium Room: 307 Title: Radiopure Plastics: Shining Light on Backgrounds Abstract: Observing neutrinoless double-beta decay (0νββ) would confirm the neutrino has a Majorana nature and offer critical evidence to understanding the universe’s matter/antimatter asymmetry. The LEGEND collaboration targets half-lives greater than T1/2>1028 years using the high-purity germanium (HPGe) detectors enriched in the isotope 76Ge. Achieving this unprecedented sensitivity – 18 orders of magnitude beyond the age of the universe – requires a detector environment with exceptionally low background radiation. While HPGe detectors are central to the measurement, sensitivity to 0νββ decay hinges on the scintillating materials surrounding them to actively detect and reject ambient background radiation. This seminar explores the critical role of radiopure scintillating materials in LEGEND, focusing on poly(ethylene-2,6-naphthalate) (PEN). We will present technical results detailing the radiopurity, scintillation performance, and mechanical stability of these materials, highlighting their successful deployment as both a structural element and an active background veto in LEGEND-200. Furthermore, we will detail ongoing efforts in additive manufacturing to realize complex, ultra-pure components for the future LEGEND-1000 phase. Beyond these technical results, we will discuss the opportunities of cross-disciplinary collaboration, bridging the fields of material science and particle physics to solve unique and complex challenges vital for fundamental discovery. This talk will conclude with a discussion on the communication journey of working on an “enabling technology” within the framework of a large-scale collaboration, with insights on how to effectively communicate the profound scientific impact of support technologies.