Speaker
Description
The neutron diagnostics on ITER are essential for the measurement of the fusion power with high accuracy and temporal resolution. The neutron diagnostics will be equipped with a variety of detectors including fission chambers, diamond and germanium detectors and scintillators. These detectors are known for their accuracy and stability, making them suitable for high-radiation environments.
Fission chambers are used in the design of neutron flux monitors and neutron cameras thanks to their high sensitivity and compatibility with nuclear environments. Fission chambers on ITER will be coated with uranium-235 or high-purity uranium-238 for higher sensitivity to either DD (2.45 MeV) or DT (14.1 MeV) neutrons. Their resilience to high-radiation fields and broad dynamic range make fission chambers an essential tool for applications in fusion power control and neutron profile measurements on ITER. Diamond and germanium detectors are suitable for applications requiring high energy resolution. Germanium detector will be used in the ITER Neutron Activation System to quantify the fluence on ITER first wall. Diamond detectors will be used in the neutron cameras and high-resolution spectrometers to provide accurate measurements of the DT source neutron spectrum. Scintillators are highly-sensitive but they require shielding from the high magnetic field fluctuations present in tokamaks.
Specific characterization of the ITER neutron detectors will improve the measurement accuracy and reduce the impact of biases in the measurements. The characterization of neutron detectors will involve a comprehensive analysis of detectors energy resolution for different types of radiation and their sensitivity. Optimization of these parameters will allow the development of reliable systems for various applications, including radiation monitoring, plasma control and safety.
Disclaimer: The views and opinions expressed herein do not necessarily reflect those of the ITER Organization.
