A diamond based neutron spectrometer for diagnostics of deuterium-tritium fusion plasmas

Journal Article · Sat Nov 15 04:00:00 EST 2014 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.4885356· OSTI ID:22308933

Nocente, M.; Gorini, G. ^[1]; Rebai, M.; Giacomelli, L. ^[1]; Tardocchi, M.; Croci, G.; Grosso, G. ^[2]; Calvani, P.; Girolami, M.; Trucchi, D. M. ^[3]; Griesmayer, E. ^[4]; Pillon, M. ^[5]

---

1. University of Milano Bicocca, Piazza della Scienza 3, Milano (Italy)
2. Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, via Roberto Cozzi 53, Milano (Italy)
3. CNR-ISM, Research Area Roma 1, Via Salaria km 29.300, 00015-Monterotondo Scalo (Rm) (Italy)
4. Atominstitut, Vienna University of Technology, Vienna (Austria)
5. Associazione EURATOM-ENEA sulla Fusione ENEA C.R. Frascati, Via E. Fermi, 45, 00044 Frascati (Roma) (Italy)

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 (<30 ns), which are essential to enable high counting rate (>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 the {sup 12}C(n, α){sup 9}Be reaction occurring between neutrons and {sup 12}C nuclei in the detector. The measured energy resolution (2.5% FWHM) meets the requirements for neutron spectroscopy applications in deuterium-tritium plasmas.

• OSTI ID: 22308933
• Journal Information: Review of Scientific Instruments, Journal Name: Review of Scientific Instruments Journal Issue: 11 Vol. 85; ISSN 0034-6748; ISSN RSINAK
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
CARBON 12
CARBON 12 TARGET
COUNTING RATES
DEUTERIUM
DIAMONDS
EFFICIENCY
ENERGY RESOLUTION
MONOCRYSTALS
NEUTRON BEAMS
NEUTRON DETECTORS
NEUTRON GENERATORS
NEUTRON SPECTROMETERS
NEUTRON SPECTROSCOPY
PLASMA
RADIATION HARDNESS
READOUT SYSTEMS
RESPONSE FUNCTIONS
SIGNALS
TOKAMAK DEVICES
TRITIUM