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Updated: Jul 1, 2026
09:49
An Experimental Protocol for Femtosecond NIR/UV - XUV Pump-Probe Experiments with Free-Electron Lasers
Published on: October 23, 2018
Neutron emission and fast ion simulation for high performance long pulses at EAST
D K Yang1, Y M Zhang1, M Xiao2
1State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, China.
The Review of Scientific Instruments
|July 10, 2021
Summary
Neutron emission spectroscopy and yield are crucial for high power heating in EAST fusion plasmas. Simulations using TRANSP with diagnostic data evaluated different neutral beam injection configurations, assessing their impact on plasma performance.
Area of Science:
- Nuclear Fusion Science
- Plasma Physics
- Tokamak Engineering
Background:
- High power heating is essential for achieving fusion conditions in tokamaks.
- Neutron emission diagnostics are key indicators of fusion reactions and plasma performance.
- Neutral Beam Injection (NBI) is a primary heating method in fusion devices like the Experimental Advanced Superconducting Tokamak (EAST).
Purpose of the Study:
- To evaluate the effects of different Neutral Beam Injection (NBI) heating configurations on EAST fusion plasmas.
- To analyze the time-dependent fast ion distribution and neutron emission characteristics.
- To validate simulation results with experimental measurements for improved understanding of NBI heating.
Main Methods:
- Utilized the TRANSP code integrated with time-dependent diagnostic results for plasma simulations.
- Simulated 30-second long pulse deuterium plasma discharges in the EAST tokamak.
- Employed neutron emission spectroscopy and neutron yield measurements, validated by a 235U fission chamber.
Main Results:
- Obtained time-dependent fast ion distribution, neutron emission spectrum, and total neutron emission rate.
- Quantified the impact of various NBI heating configurations on neutron yields.
- Demonstrated the correlation between NBI deposition and neutron production in deuterium plasmas.
Conclusions:
- The study successfully simulated NBI heating effects in EAST, providing insights into plasma performance.
- Accurate simulation of neutron emission is vital for optimizing NBI heating strategies.
- The methodology offers a robust approach for evaluating fusion plasma heating in future experiments.
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