Neutron spectrometer for ITER using silicon detectors
2008 (English)In: Review of Scientific Instruments, ISSN 0034-6748, E-ISSN 1089-7623, Vol. 79, no 10, 10E508- p.Article in journal (Refereed) Published
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(-4) n cm(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(9) n cm(-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.
Place, publisher, year, edition, pages
2008. Vol. 79, no 10, 10E508- p.
neutron spectrometers, plasma diagnostics, Tokamak devices
IdentifiersURN: urn:nbn:se:uu:diva-149437DOI: 10.1063/1.2957930ISI: 000260573500090OAI: oai:DiVA.org:uu-149437DiVA: diva2:405021
Conference Information: 17th Topical Conference on High-Temperature Plasma Diagnostics
Albuquerque, NM, 2008 2011-03-202011-03-202011-03-20Bibliographically approved