The 2nd Technical Meeting on the Collisional-Radiative Properties of Tungsten and Hydrogen in Edge Plasma of Fusion Devices, will be held from 28 November – 1 December 2023 at IAEA. The Scientific Secretary is Kalle HEINOLA.

For registration and abstract submission, please see the Indico meeting page.

The IAEA is committed to the promotion of gender equality in all its activities and qualified women scientists are particularly encouraged to participate in the meeting.

Introduction

Tungsten is currently the most prominent candidate to be used as an armour material in the first wall components of future fusion power plants. It has excellent physical and thermomechanical properties to withstand the extreme conditions necessary for fusion, including high heat gradients and particle fluxes from the reactor’s hydrogen plasma fuel. However, even small amounts of ejected tungsten material off the components’ surfaces can be detrimental to the hydrogen plasma operation. In order to perform predictive simulations of plasma performance incorporating tungsten impurities and to characterise the tungsten source originating from the wall components, validated and evaluated atomic and molecular data must be used as input in the simulations.

This Technical Meeting on Tungsten and Hydrogen in Edge Plasmas brings together physicists from a broad range of fusion research domains to discuss and share information on the current understanding of physics and data requirements for tungsten and hydrogen plasma interactions. The goal is to provide a forum for information exchange between i) fusion experimentalists utilizing linear plasma and magnetic fusion devices as well as researchers performing fundamental laboratory experiments, and ii) physicists performing edge plasma simulations as well as theorists providing fundamental atomic, molecular and plasma-wall interaction data for fusion. Participants are invited to propose a presentation of their research, either as an oral contribution or as a poster.

Objectives

• Knowledge-sharing and networking between fusion researchers and plasma scientists in different domains to identify commonalities, foster collaboration and share opportunities.
• Training and instruction of early-stage career researchers in experimental and theoretical tools used in research of plasma-particle processes taking place in edge plasma regions of a fusion reactor.
• Discussion and review of emerging research areas in fusion physics and science specifically related to atomic and molecular edge plasma processes and plasma-wall processes incorporating tungsten and hydrogen.
• Proceedings of the meeting to be made available in a suitable journal publication.

Target Audience

Research scientists related to nuclear fusion, at any stage of their career, who are involved in the quantitative and qualitative study, analysis, modelling or prediction of collisional-radiative properties or plasma-wall interactions of tungsten and hydrogen in fusion devices, using or producing fundamental data on these processes. Experimental and theoretical approaches are welcomed.

The IAEA is committed to the promotion of gender equality in all its activities and qualified women scientists are particularly encouraged to participate in the meeting.

 Topics

• Missing tungsten and hydrogen data in magnetically-confined edge plasma models
  • Rates for ionization, recombination and excitation
  • Multi-step ionization and excitation
  • Non-resonant charge exchange
• Recommended tungsten and hydrogen data for edge plasma modelling
  • Addressing the large scatter in the various sets for W atomic data (in particular excitation rates)
  • Hydrogen molecular data: vibrationally-, rotationally- and isotopically-resolved data; mixed molecules; limited data available for T₂, TH and TD
  • Metastable states of W
  • Uncertainties of W and hydrogen data
• The inclusion of reduced photon opacity information in collisional-radiative models
  • Revised CRM with (semi)opaque lines
  • Full non-linear model or a reduced CRM
  • Isotope effects of collisional broadening in high plasma density
  • Wall reflection models for photons: on W and Be or deposited layers; surface roughness effects
• Data needs for ITER: CR and plasma-wall interactions with W and hydrogen
  • Accuracy improvement for ionization, recombination, radiation and CX rates of W
  • CR: to obtain reliable charge distribution of W for modelling W upstream migration and penetration to core plasma
  • Spectral lines of interest W⁰ to at least W⁶⁴⁺
  • Dielectronic recombination rates and photon opacity for W vapour shielding during fast transients

Guide for Meeting Participants