Development of Barium Tagging: A Background Free Method to Search for Majorana Neutrinos
A robust observation of neutrinoless double beta decay is currently the most sensitive method to determine the Majorana nature of the neutrino. The detection of the single barium ion produced as a result of the double beta decay of xenon 136 would enable a new class of ultra-low background neutrinoless double beta decay experiments. However, despite 19 years of R&D, a credible method to collect and identify individual barium ions in bulk xenon has remained elusive.
The NEXT experiment is exploring the possibility of utilizing Single Molecule Fluorescent Imaging (SMFI), a Nobel prize winning technique, in a High Pressure Gas Xenon (HPGXe) TPC to accomplish this feat. This R&D adapts techniques from biochemistry and microscopy to yield a novel technology with potential to extend the sensitivity of neutrinoless double beta decay searches. We will present on recent developments and current status including the development and testing of custom dry-phase molecules and the resolution of individual ions in a high pressure noble environment.