EPJ Techniques and Instrumentation最新文献

Accelerator Mass Spectrometry (AMS) adds the techniques of higher energy charged particle acceleration to the basic principles of Isotope Ratio Mass Spectrometry (IRMS) to provide extremely low detection capability (below 1 femtogram) of rare isotopes in samples of natural materials as small as 1 mg. Depending on the element selected and the configuration of the equipment, rare isotope sensitivities can reach less than one part in 10¹⁵. The advantages of this small sample size and high sensitivity for the detection of rare isotopes include a) the economic benefit of collecting, shipping and preparing much smaller samples, and b) the ability to analyse specific chemical compounds within the sample. For the latter advantage, the pathway taken by that compound through a complex system can be more precisely traced or, in the case of radioactive isotopes, more precise chronological information can be provided. The paper is an amplification of material which was presented at the IAEA International Conference on Accelerators for Research and Sustainable Development: novel concepts and technical innovation. It begins with a basic overview of AMS technology, with an emphasis on how the use of higher energy contributes to this enhanced sensitivity, and then provides several examples of new AMS technologies which reduce the energy and space requirements for such systems. Several examples of applications which contribute to the investigation of sustainability in other areas of environmental concern are then briefly described.

New modes of production and supply of short-lived radioisotopes using accelerators are becoming attractive alternatives to the use of nuclear reactors. In this study, the use of a compact accelerator neutron source (CANS) was implemented to explore the production of ^99mTc and ¹⁰¹Tc. Irradiations were performed with neutrons generated from a 16.5 MeV cyclotron utilising the ¹⁸O(p, n)¹⁸F reaction during routine ¹⁸F-fluorodeoxyglucose (FDG) production in a commercial radiopharmacy. Natural molybdenum targets in metal form were employed for the production of several Tc isotopes interest via (n, γ) reactions on ⁹⁸Mo and ¹⁰⁰Mo. The production of ^99mTc and ¹⁰¹Tc under these conditions is considered and discussed.

The interest in compact, cost-effective, and versatile accelerators is increasing for many applications of great societal relevance, ranging from nuclear medicine to agriculture, pollution control, and cultural heritage conservation. For instance, Particle Induced X-ray Emission (PIXE) is a non-destructive material characterization technique applied to environmental analysis that requires MeV-energy ions. In this context, superintense laser-driven ion sources represent a promising alternative to conventional accelerators. In particular, the optimization of the laser-target coupling by acting on target properties results in an enhancement of ion current and energy with reduced requirements on the laser system. Among the advanced target concepts that have been explored, one appealing option is given by double-layer targets (DLTs), where a very low-density layer, which acts as an enhanced laser absorber, is grown to a thin solid foil. Here we present some of the most recent results concerning the production with deposition techniques of advanced DLTs for laser-driven particle acceleration. We assess the potential of these targets for laser-driven ion acceleration with particle-in-cell simulations, as well as their application to PIXE analysis of aerosol samples with Monte Carlo simulations. Our investigation reports that MeV protons, accelerated with a ∼20 TW compact laser and optimized DLTs, can allow performing PIXE with comparable performances to conventional sources. We conclude that compact DLT-based laser-driven accelerators can be relevant for environmental monitoring.