Half-life measurements of $^{212}$Po with thorium-loaded liquid scintillator

TL;DR

This study measures the half-life of $^{212}$Po using a thorium-loaded liquid scintillator and advanced signal processing, achieving a preliminary value with ongoing efforts to improve accuracy.

Contribution

It introduces a novel liquid scintillator setup with complex doping and develops algorithms for precise decay event pairing to measure $^{212}$Po half-life.

Findings

Preliminary half-life measured as 294.8 ± 1.9 ns.

Use of thorium-loaded scintillator for decay detection.

Ongoing improvements aim to reduce uncertainties.

Abstract

Precise measurement of half-life of $^{212}$Po (one of the daughter nuclides in radioactive chain of $^{232}$Th) was realized by means of liquid scintillator based on toluene doped by complex of thorium and trioctylphosphine oxide with concentration of Th $\sim0.1$ mass %. Fast photomultiplier tube and high frequency oscilloscope were used to acquire the scintillation signals waveforms. The algorithms were developed to find pairs of $^{212}$Bi beta-decays and subsequent $^{212}$Po alpha-decays, to calculate time differences between the events in the pair, and to build $^{212}$Bi beta-decay and $^{212}$Po alpha-decay energy spectra. Preliminary the $^{212}$Po half-life is $T_{1/2} = (294.8 \pm 1.9)$ ns. The experiment is in progress aiming at reduction of the statistical and systematic uncertainties.