Effect of detachment on Magnum-PSI ELM-like pulses: II. Spectroscopic analysis and role of molecular assisted reactions
arxiv(2023)
摘要
The linear plasma machine Magnum-PSI can replicate similar conditions to
those found in a tokamak at the end of the divertor leg. A dedicated capacitor
bank, in parallel to the plasma source, can release a sudden burst of energy,
leading to a rapid increase in plasma temperature and density, resulting in a
transient heat flux increase of half of an order of magnitude, a so called
ELM-like pulse. Throughout both the steady state and the pulse, the neutral
pressure in the target chamber is then increased, causing the target to
transition from an attached to a detached state. In the first paper related to
this study direct measurements of the plasma properties are used
to qualitatively determine the effect of detachment on the ELM-like pulse. This
is used to show the importance of molecular assisted reactions. Molecular
processes, and especially molecular activated dissociation, are found to be
important in the exchange of potential energy with the plasma, while less so in
radiating the energy from the ELM-like pulse. At low target chamber pressure,
the plasma generated via ionisation during the part of the ELM-like pulse with
the higher temperature is more than that produced by the plasma source, a
unique case in linear machines. At high target chamber pressure molecular
activated recombination contributes up to a third of the total recombination
rate, contributing to the reduction of the target particle flux. Some metrics
that estimate the energy lost by the plasma per interactions with neutrals,
potentially relevant for the portion of the tokamak divertor leg below
∼10eV, are then tentatively obtained.
更多查看译文
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要