Benjamin Jones

High Pressure Xenon Gas TPCs with Single Barium Ion 
Identification:  Progress Toward the first Ton-Scale, Background Free Neutrinoless Double Beta Decay Experiment

Abstract:

The goal of future neutrinoless double beta decay experiments is to achieve sufficient sensitivity to establish 
the Majorana nature of the neutrino, probing decay rates substantially smaller than 10-27 per year. Such a discovery 
would have major implications for cosmology and particle physics, but requires ton-scale detectors with backgrounds below 
1 count per ton per year in the signal ROI. This is a formidable technological challenge without a known solution. This 
talk will focus on a technology that shows particular promise: the High Pressure Xenon Gas TPC (HPGXe-TPC). In HPGXe-TPCs 
such as the US/Spanish led NEXT experiment, event topology and precise energy resolution provide particularly strong background 
rejection capabilities.  Ongoing work on SMFI-based barium tagging, combining techniques from biochemistry, microscopy and nuclear 
physics, may further suppress radioactive backgrounds, perhaps enabling the first background-free, ton-scale technology. This talk
will cover early results from the running NEXT-NEW demonstrator, and present new demonstrations of barium tagging methods developed
for NEXT with the unprecedented combination of single ion sensitivity and plausible scalability to large experiments.