Neutron spectrometer for ITER using silicon detectors

Journal Article · Wed Oct 15 04:00:00 EDT 2008 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.2957930· OSTI ID:21266497

Conroy, Sean W; Weiszflog, Matthias; Andersson-Sunden, Erik; Ericsson, Goran; Gatu-Johnson, Maria; Hellesen, Carl; Ronchi, Emanuel; Sjostrand, Henrik ^[1]

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1. Department of Physics and Astronomy, Uppsala University, EURATOM-VR, Uppsala 75120 (Sweden)

High resolution neutron spectrometers provide information about plasma parameters at existing fusion experiments. Such a system may also be employed at ITER. Proton recoil telescopes have classically been used to detect neutrons with good energy resolution but poor efficiency. Using annular silicon detectors, it is possible to greatly increase the solid angle coverage and hence improve efficiency. Based on a simulation (MCNPX) study, the scaling of energy resolution, efficiency, and time to determine an ion temperature to 10% accuracy on foil thickness and detector location is shown. The latter quantity is used to determine the optimum foil thickness and detector geometry for specific plasma temperatures. For a 20 keV deuterium-tritium (DT) plasma, 5.3% resolution with efficiency of 2.9x10{sup -4} n cm{sup 2} is attainable using the available detectors. This gives a temperature measurement with 10% accuracy in 1.1 ms for a neutron flux of 2x10{sup 9} n cm{sup -2}. Multiple detectors can be used to further increase the efficiency if needed. A system of this kind could be tested in a future DT campaign at, for example, JET.

• OSTI ID: 21266497
• Journal Information: Review of Scientific Instruments, Journal Name: Review of Scientific Instruments Journal Issue: 10 Vol. 79; ISSN 0034-6748; ISSN RSINAK
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
ACCURACY
DEUTERIUM
EFFICIENCY
ELECTRON TEMPERATURE
ENERGY RESOLUTION
ION TEMPERATURE
ITER TOKAMAK
KEV RANGE 10-100
NEUTRON FLUX
NEUTRON SPECTROMETERS
NEUTRONS
PLASMA DIAGNOSTICS
PROTONS
SI SEMICONDUCTOR DETECTORS
SIMULATION
TEMPERATURE MEASUREMENT
THICKNESS
TRITIUM