Speaker
Description
Demonstrating a selective, high-efficiency barium tagging system would drive backgrounds in neutrinoless double-beta decay (0νββ) searches with xenon time-projection chambers to near-zero at multi-ton scale. The NEXT Collaboration is pursuing a phased program that builds on the excellent energy resolution and topological discrimination of high-pressure xenon gas TPCs, while developing a future barium-tagging stage based on single-molecule fluorescence imaging (SMFI).
In this poster, we present recent advances toward a complete end-to-end Ba²⁺ tagging chain, including molecularly engineered surface chemistry with functionalized monolayers that enable selective capture and controlled measurement of Ba²⁺ at an optical sensor, SMFI in a high-pressure gas microscope using organic fluorophores optimized for dry phase operation and single-ion sensitivity, and possibly a four-phase RF-carpet system designed for efficient, robust transport of the daughter ion to the sensors.