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Strategy for the absolute neutron emission measurement on ITER
M Sasao1, L Bertalot, M Ishikawa
1Department of Quantum Science and Energy Engineering, Tohoku University, Sendai 980-8579, Japan. mamiko.sasao@qse.tohoku.ac.jp
The Review of Scientific Instruments
|November 2, 2010
Summary
Achieving 10% accuracy in ITER fusion measurements requires calibrated neutron diagnostics. A high-strength neutron generator (10^10 n/s for DT, 10^8 n/s for DD) is essential for calibrating various systems.
Area of Science:
- Nuclear fusion energy research
- Plasma physics diagnostics
Background:
- ITER requires precise absolute fusion measurements, demanding 10% accuracy.
- Current diagnostic systems necessitate robust calibration strategies for reliable data acquisition.
Purpose of the Study:
- To determine the requirements for calibrating ITER's neutron measurement subsystems.
- To identify suitable neutron sources and estimate calibration durations.
Main Methods:
- Neutron transport calculations were performed to assess calibration source requirements.
- Evaluated the necessary source strength for Deuterium-Tritium (DT) and Deuterium-Deuterium (DD) neutron generators.
- Estimated the time required for calibrating flux monitors, profile monitors, and the activation system.
Main Results:
- A DT neutron generator with a source strength exceeding 10^10 neutrons/second is suitable for calibration.
- A DD neutron generator with a source strength exceeding 10^8 neutrons/second is suitable for calibration.
- Minimum calibration time for all systems is estimated at eight weeks.
Conclusions:
- A high-intensity neutron generator is critical for accurate calibration of ITER's neutron diagnostics.
- The proposed calibration approach ensures the required 10% accuracy for fusion measurements.
- The calibration process, utilizing a suitable neutron source, will take a minimum of eight weeks.
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