SABRE South, a 35-50 kg NaI(Tl) detector with a liquid scintillator veto at the Stawell Underground Physics Laboratory, is projected to reach 5 sigma discovery or 3 sigma exclusion of the DAMA/LIBRA annual modulation after two years, assuming a total background of 0.72 cpd/kg/keV.
High sensitivity characterization of an ultra-high purity NaI(Tl) crystal scintillator with the SABRE proof-of-principle detector
1 Pith paper cite this work. Polarity classification is still indexing.
abstract
We present new results on the radiopurity of a 3.4-kg NaI(Tl) crystal scintillator operated in the SABRE proof-of-principle detector setup. The amount of potassium contamination, determined by the direct counting of radioactive $^{40}$K, is found to be $2.2\pm1.5$ ppb, lowest ever achieved for NaI(Tl) crystals. With the active veto, the average background rate in the crystal in the 1-6 keV energy region-of-interest (ROI) is $1.20\pm0.05$ counts/day/kg/keV, which is a breakthrough since the DAMA/LIBRA experiment. Our background model indicates that the rate is dominated by $^{210}$Pb and that about half of this contamination is located in the PTFE reflector. We discuss ongoing developments of the crystal manufacture aimed at the further reduction of the background, including data from purification by zone refining. A projected background rate lower than $\sim$0.2 counts/day/kg/keV in the ROI is within reach. These results represent a benchmark for the development of next-generation NaI(Tl) detector arrays for the direct detection of dark matter particles.
fields
physics.ins-det 1years
2024 1verdicts
CONDITIONAL 1representative citing papers
citing papers explorer
-
The SABRE South Technical Design Report Executive Summary
SABRE South, a 35-50 kg NaI(Tl) detector with a liquid scintillator veto at the Stawell Underground Physics Laboratory, is projected to reach 5 sigma discovery or 3 sigma exclusion of the DAMA/LIBRA annual modulation after two years, assuming a total background of 0.72 cpd/kg/keV.