Neutron-induced signal on the single crystal chemical vapor deposition diamond-based neutral particle analyzer
- 1 November 2020
- journal article
- research article
- Published by AIP Publishing in Review of Scientific Instruments
- Vol. 91 (11), 113304
- https://doi.org/10.1063/5.0020460
Abstract
A diamond-based neutral particle analyzer (DNPA) array composed of single-crystal chemical vapor deposition (sCVD) diamond detectors was installed on the Large Helical Device (LHD) for measuring the helically trapped energetic particles. In high neutron flux experiments, the unwanted neutron-induced pulse counting rate should be estimated using the neutron diagnostics because a diamond detector is sensitive to neutrons as well as energetic neutral particles. In order to evaluate the quantitative neutron-induced pulse counting rate on the DNPA, the response functions of the sCVD diamond detector for mono-energetic neutrons were obtained using accelerator-based D–D and D–7Li neutron sources in Fast Neutron Laboratory (FNL). As a result of the neutron flux estimation by the Monte Carlo N-Particle code at the NPA position in the LHD and the response function obtained in the FNL experiment, the counting rate of the neutron-induced signal was predicted to be 1.1 kcps for the source neutron emission rate of Sn = 1 × 1015 n/s. In the LHD experiment, the neutron-induced signals were observed by closing the gate valve during the plasma discharges. It is found that the counting rates of the neutron-induced signals proportional to Sn reached 1.1 kcps at Sn = 1 × 1015 n/s. As a result of the quantitative estimation of the neutron-induced signals on the DNPA using other neutron measurements, it has become possible to accurately measure energetic neutral particles in the high neutron flux experiment.Funding Information
- National Institute for Fusion Science (KOAH037, KOAA001, ULRR006, ULRR035, ULRR703, 0131190)
This publication has 27 references indexed in Scilit:
- Neutron Diagnostics in the Large Helical DeviceIEEE Transactions on Plasma Science, 2018
- Design and calibration of a neutral particle analyzer for the KSTARFusion Engineering and Design, 2011
- A novel silicon detector for neutral particle analysis in JET fusion researchNuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2008
- Compact multichannel neutral particle analyzer for measurement of energetic charge-exchanged neutrals in Alcator C-ModReview of Scientific Instruments, 2006
- Application of natural diamond detector to energetic neutral particle measurements on NSTXReview of Scientific Instruments, 2003
- Charge exchange neutral particle analysis with natural diamond detectors on LHD heliotronReview of Scientific Instruments, 2001
- Development and energy calibration of Si-FNA for LHD fast ion measurementReview of Scientific Instruments, 2001
- Tokamak Fusion Test Reactor charge exchange atom spectrometry using a natural diamond detectorReview of Scientific Instruments, 1999
- Application of silicon surface barrier detector for fast neutral particlesReview of Scientific Instruments, 1985
- A neutral-particle analyser for plasma diagnosticsJournal of Physics E: Scientific Instruments, 1978