Proceedings of the International Symposium on Plasma Wall Interaction

Contents

Foreword

Opening of the Conference

Welcome Address

Session A - Plasma in Interaction with the Wall

Recent Results on Plasma-Wall Interaction in the T.F.R. Tokamak

Divertors for Impurity Control and Review of Impurity Effects in PPL Tokamaks

A Review of Work on Plasma-Wall Interactions and Divertor Experiments on DITE

Energy Flux and Surface Temperature Measurements at Surfaces in the DITE Tokamak

Wall Analysis in T.F.R. Performed by QWAASS

Plasma-Wall Charge-Exchange Interactions in the 2XIIB Magnetic Mirror Experiment

Effect of Neutral Injection Heating on the Impurity Level in the W VII A Stellarator

Review of the Work on Plasma-Wall Interaction in Tokamak Plasma Confinement at JAERI

Surface and Impurity Studies in ORMAK and ISX

Alumina-Plasma Interaction in the PETULA Tokamak

Modeling in the Edge of a Tokamak Plasma

Kinetic Theory of Plasma in the Limiter-Shadow Region

Screening Property of the Limiter Shadow Region for Heavy Wall Impurities

Protection of Walls from Hard Disruptions in Large Tokamaks

The Effect of Electric Field in the Divertor Scrape-Off Layer

Review of the Work on Impurities and Plasma-Wall Interaction on the Pulsator Tokamak

Neutral Particle Emission of the Pulsator Plasma During High-Density Discharges

Models for Impurity Production and Transport in Tokamaks

Investigation of Plasma-Wall Interaction by the Aid of a Plasma Accelerator

Session B - Impurity Content, Transport and Effects

Impurity Transport in Tokamaks

Atomic Rate Coefficients for Tokamak Plasmas

Numerical Investigation of the Radial Impurity Transport in Tokamak Plasmas

Collision-Dominated Multi-Ion Diffusion

Relative Importance of Different Impurity Sources in Tokamak Reactors as Estimated from Particle Balance Equations

Suppression of the Internal Disruption in a Tokamak by Neutral Injection Heating

Sputtering and Neutral Injection Heating

The Plasma Instabilities due to Impurity Ions

Energy and Angular Distribution of Bremsstrahlung Flux from Tokamak Plasmas

Session C - Surface Effects

Arcing Surface Phenomena

Methane Formation During Hydrogen Ion Irradiations of Silicon and Boron Carbides

Interaction of Boron Materials with a Hydrogen Plasma

Laser Induced Desorption as a Method to Study the Interaction of Gases with Metal Surfaces

Thermochemie von Reaktionen der Metalle Nb, V und Mo mit Restgasen des Vakuums

Interaction of Thermal Hydrogen Atoms with Stainless Steel and Graphite

Induced Desorption from 316 L Stainless Steel

Desorption of Surface Contaminants by Low-Energy Particle Impact

Erosion and Changes in Surface Composition of Stainless Steel 316 after Low Energy Light Ion Bombardment at Temperatures Between 50 and 660°C

Sputtering Yields of Graphite Using Microbalance Technique with keV Region He+, H+

Sputtering Yields for 0.1-6 keV Protons Incident onto Molybdenum and Graphite Targets

Plasma Generation by Gas Ionization in Radial Electric and Axial Magnetic Fields

The Role of Trapping Reflection and Diffusive Re-emission in the Recycling of Plasmas at Surfaces

Wall Erosion by Physical and Chemical Sputtering and Blistering

Plasma Wall Interactions, Glow Discharge Experiences for Fusion Reactor Studies

Outgassing of Inconel and Some Low-Z Materials

Semiempirical Theory on the Dependence of Blistering and Exfoliation on Radiation Swelling and Gas Pressure

Blister Formation in Multiple Energy He Implanted Stainless Steel

Blistering of Monocrystalline Vanadium by 10 keV Helium Ions

Surface Erosion of Stainless Steel and Molybdenum by Low Energy High Dose He+ Bombardment

Helium Profiles in Niobium and Molybdenum

Crystal Lattice Stress in Pyrolytic Graphite Irradiated with 4 MeV Helium Ions

Energy Reflections from Nb, Ag, and Au Bombarded with 1 - 10 keV Protons

Optical Radiation from Hydrogen and Helium Scattered from Solid Surfaces

Cleaning of Large Metallic Vessels for Plasma Confinement Devices

Session D - Diagnostic Methods

Mass Spectrometric Measurements of Gas Release due to Plasma Wall Interactions in the DITE Tokamak

Mass Spectroscopy in the TFR Machine

The Role of Wall-Adsorbed Hydrogen in Tokamak Discharges

Detection of Low Densities of Metal Atoms by Pulsed, Dye Laser Excited Fluorescence Spectroscopy

Possible Applications of Atomic Fluorescence Spectroscopy in CTR Using CW Dye Lasers

Special Problems in the Density Measurements of Sputtered Iron by Fluorescence Spectroscopy

Detection of Neutral Hydrogen and Light Impurities by Resonance Scattering in the Vacuum Ultraviolet

Low Energy Ion Scattering Study of Adsorbed Layers on Stainless Steel Surface

Rauheitsuntersuchungen an Oberflachen mit dem Raster-Elektronenmikroskop (REM)

Session E - Control of Plasma Wall Interaction

The Effect of Cleaning and Other Surface Treatments on the Surface Composition of Technological Materials

Cleaning of Large Metallic Vessels for Plasma Confinement Devices

Mass Spectrometric Measurements of Gas Release due to Plasma Wall

Interactions in the DITE Tokamak

Plasma Wall Interaction in DIVA

On Toroidal Divertors for Tokamaks

Experimental Studies on the Methods of Surface Cleaning for Tokamak Devices

Wall Conditioning Studies for ORMAK and ISX

First Wall Surface Treating in the Frascati Tokamak FT

Method of Controlling Impurity Transport

Impurity Control in Near-Term Tokamak Reactors

On Mechanical Divertors (Scrape-Off-Limiters)

Disappearance of Hard-Rays from a Tokamak Plasma by ADDUcation of a Fast-Changing Magnetic Pulse

Plasmas with Cold Blankets

Gas-Blanket Studies in a Toroidal Discharge

Experimental Results on the Penetration of Sputtered Atoms into a Neutral Gas Blanket

Plasma-Wall Interactions

Stationary-State Profiles in a Cylindrical Hydrogen Arc in a Gas Blanket

Numerical Investigation of the Behaviour of Neutrals in the Wall Region of High Temperature Plasmas

Session F - First Wall Problems in Future Large Confinement Devices

On the Choice of the First Wall Material for the J.E.T. Experiment

The PDX Experiment

Control of Plasma Wall Interaction in the ASDEX Divertor Tokamak

JT-4 Program

List of Participants

Subject Index