Single crystal Diamond Detectors (SDD) are being increasingly exploited for neutron diagnostics in high power fusion devices, given their significant radiation hardness and high energy resolution capabilities. The geometrical efficiency of SDDs is limited by the size of commercially available crystals, which is often smaller than the dimension of neutron beams along collimated lines of sight in tokamak devices. In this work, we present the design and fabrication of a 14 MeV neutron spectrometer consisting of 12 diamond pixels arranged in a matrix, so to achieve an improved geometrical efficiency. Each pixel is equipped with an independent high voltage supply and read-out electronics optimized to combine high energy resolution and fast signals (1 MHz) spectroscopy. The response function of a prototype SDD to 14 MeV neutrons has been measured at the Frascati Neutron Generator by observation of the 8.3 MeV peak from the12C(n, α)9Be reaction occurring between neutrons and12C nuclei in the detector. The measured energy resolution (2.5% FWHM) meets the requirements for neutron spectroscopy applications in deuterium-tritium plasmas. © 2014 Euratom.
All Science Journal Classification (ASJC) codes
Cazzaniga, C., Nocente, M., Rebai, M., Tardocchi, M., Calvani, P., Croci, G., Giacomelli, L., Girolami, M., Griesmayer, E., Grosso, G., Pillon, M., Trucchi, D. M., & Gorini, G. (2014). A diamond based neutron spectrometer for diagnostics of deuterium-tritium fusion plasmas. Review of Scientific Instruments, 85(11), -. [11E101]. https://doi.org/10.1063/1.4885356