Characterization of scintillator materials for fast-ion loss detectors in nuclear fusion reactors

摘要

In fusion plasma reactors, fast ion generated by heating systems and fusion born particles must be well confined. The presence of magnetohydrodynamic (MHD) instabilities can lead to a significant loss of these ions, which may reduce drastically the heating efficiency and may cause damage to plasma facing components in the vacuum vessel. In order to understand the physics underlying the fast ion loss mechanism, scintillator based detectors have been installed in several fusion devices. In this work we present the absolute photon yield and its degradation with ion fluence in terms of the number of photons emitted per incident ion of several scin-tillators thin coatings: SrGa_2S_4:Eu~(2+) (TG-Green), Y_3Al_5O_(12):Ce~(3+) (P46) and Y_2O_3:Eu~(3+) (P56) when irradiated with light ions of different masses (deuterium ions, protons and a-particles) at energies between approximately 575 keV and 3 MeV. The photon yield will be discussed in terms of the energy deposited by the particles into the scintillator. For that, the actual composition and thickness of the thin layers were determined by Rutherford Backscattering Spectrometry (RBS).