Fusion science and technology present interesting answers as Cambodia looks to diversify its energy sources and move toward sustainable ones. This abstract examines how important it is to advance fusion research in Cambodia by using data on atomic, molecular, and plasma-material interactions. The process of fusion, which uses the energy of atomic nuclei, has enormous potential for producing...
It appears that a partially ionized plasma is formed around any protruded interface of different material phases in a fusion plasma. Such interface potentially and intrinsically releases neutral gas from outgassing, sputtering and evaporation, and ablated vapor from solid, for examples dust, sublimated plasma facing components (PFC), and liquid, for examples molten droplets, liquid PFCs,...
The present study has determined excitation energy of the 127 states of the transmutation of tungsten atoms He-like-(Hf, Ta, Re and Os). In this work, we use the ab initio MCDHF and MBPT methods implemented in GRASP2018 and FAC codes, respectively. We extend the calculation for n = 8 to improve the precision of the atomic data used in line identification, plasma modeling and diagnostics of...
The impact of varying periodic electric fields on the emission line shapes in fusion plasmas, is a subject of significant interest. Tokamak devices, universally employing radio frequency (rf) waves, aim to heat, control, or diagnose plasma through effective coupling. This research focuses on developing a spectroscopic diagnostic tool to analyze the periodic electric field's propagation within...
Molecular dynamics (MD) simulations of successive collision cascades within the same simulation domain and further defect evolution were performed using two different inter-atomic potentials (IAP) in tungsten, one EAM based and the other a `quantum accurate' machine learning potential, SNAP. The micro-structural changes are analyzed as a function of displacements per atom (dpa) up-to...
Component-scale predictive models for how hydrogen isotopes interact with, and are retained by, irradiation-induced defects are required to inform design decisions in materials for fusion power. This is a multiscale materials modelling challenge, with a conceptual gap between electronic structure calculations on one hand, which provide high accuracy estimations of idealised elemental defect...
The choice of elements in structural materials such as stainless-steel can reduce radiation levels due to particle activation. The dose rate to workers and electrical components is managed by the material used for radiation shielding. This work analyses candidate materials used in the ITER neutral beam duct. Quantitative analysis of radiation effects in the Neutral Beam Injection (NBI) section...
In this study, we present an approach for the precise determination of edge plasma density profiles in the KSTAR tokamak, leveraging Bayesian inference and Gaussian process regression techniques in conjunction with atomic data. The methodology relies on a collisional radiative model that captures the interactions between neutral deuterium beam atoms and plasma constituents. This model, built...
In magnetic fusion devices equipped with Tungsten (W) plasma-facing components (PFCs), dilution and radiation studies have become an essential feature of the experimental developments. Among several methods used to diagnose W transport and radiation in fusion plasmas, spectroscopy is one of the most powerful because it allows us to distinguish between the numerous ionisation stages of W. For...
The optical actinometric technique is used to investigate the addition of impurities in the argon and helium microwave discharges during the wall conditioning process of the MT-I spherical tokamak. This technique normalizes the change occurring in the electron energy distribution function with changing plasma conditions through the emission intensity of the selected Ar/He lines. Any change in...
The cross-sections and Maxwellian rate coefficients of electron impact single ionization is theoretically investigated for tungsten ions (W68+ to W71+) for fine structure levels of configurations containing n = 2 orbitals. Maxwellian rate coefficients for ground state are evaluated at the temperature range 20keV to 300keV. Detailed comparison between results from different approximations,...
During D-T nuclear fusion reaction, plasma-facing materials, e.g. Tungsten (W) in ITER, are exposed to a hydrogen-rich environment. Hydrogen is easily absorbed into W and alter the material behavior. Conventionally, hydrogen is well known to cause hardening behavior of materials. Solute hardening is a typical phenomenon associated with hydrogen-induced hardening and it is traditionally...
Hydrogen glow discharge cleaning (H-GDC) is a routine conditioning procedure for the present tokamaks and the future fusion machines, including the ITER. Due to the low energy of hydrogen ions in glow discharge plasmas, the probability of any considerable damage to the plasma facing components was mainly ignored among researchers in the field. In this work, Tungsten and Molybdenum, as the...
This work presents a combined theoretical and experimental approach to understand the complex surface phenomena occurring in fusion and nuclear materials.
Fusion Materials: We investigate the interaction of low-Z (lithium and boron) coatings with carbon under extreme fusion plasma conditions. A multi-scale approach using computational modeling, real-time plasma diagnostics, and ex-vessel...
Since December 2022 WEST has tested actively cooled solid W monoblock plasma facing units mounted on a flat crown forming the lower divertor. These tests aim at long plasma discharges, with thermal loads of the same order of magnitude as those expected for the ITER vertical part of the lower divertor (10 MW/m$^2$). Deuterium plasma durations of more than 360 seconds have been obtained in a...
