Study on the reusability of fluorescent nuclear track detectors using optical bleaching

TL;DR

This study demonstrates that fluorescent nuclear track detectors (FNTDs) based on Al₂O₃:C,Mg crystals can be optically bleached and reused at least seven times for high-density charged particle imaging, enhancing their practical utility.

Contribution

The paper introduces a method for optical bleaching of FNTDs, enabling their reuse in high-density imaging applications, which was not previously established.

Findings

FNTDs can be reused at least seven times with maintained performance.

Optical bleaching with 355 nm UV laser effectively resets the detector signals.

Signal-to-noise ratio remains acceptable after multiple irradiation-bleaching cycles.

Abstract

Fluorescent nuclear track detectors (FNTDs) based on Al${_2}$O${_3}$:C,Mg crystals are luminescent detectors that can be used for dosimetry and detection of charged particles and neutrons. These detectors can be utilised for imaging applications where a reasonably high track density, approximately of the order of 1 $\times$ $10^4$ tracks in an area of 100 $\times$ 100 $\mu$m$^2$, is required. To investigate the reusability of FNTDs for imaging applications, we present an approach to perform optical bleaching under the required track density conditions. The reusability was assessed through seven irradiation-bleaching cycles. For the irradiation, the studied FNTD was exposed to alpha-particles from an $^{241}$Am radioactive source. The optical bleaching was performed by means of ultraviolet laser light with a wavelength of 355 nm. Three dedicated regions on a single FNTD with different accumulated track densities and bleaching conditions were investigated. After every irradiation-bleaching cycle, signal-to-noise ratio was calculated to evaluate FNTD performance. It is concluded that FNTDs can be reused at least seven times for applications where accumulation of a high track density is required.