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Nuclear Fusion Fusion Nucleaire Nnephum Cnhte3 Fusion Nuclear nuclear fusion fusion nucleaire nnepHUM cnHTe3 fusion nuclear ATOMIC AND PLASMA-MATERIAL INTERACTION DATA FOR FUSION (Supplement to the journal Nuclear Fusion). -VOLUME 1. *|v INTERNATIONAL ATOMIC ENERGY AGENCY, VIENNA, 1991 % AGENCE INTERNATIONALE DELENERGIE ATOMIQUE, VIENNE.1991 MEWflYHAPOflHOE ATEHTCTBO nO ATOMHOM SHEPrMM, BEHA, 1991 ORGANISMO INTERNACIONAL DE ENERGIA ATOMICA, VIENA,1991 The following States are Members of the International Atomic Energy Agency: AFGHANISTAN HOLY SEE PERU ALBANIA HUNGARY PHILIPPINES ALGERIA ICELAND POLAND ARGENTINA INDIA PORTUGAL AUSTRALIA INDONESIA QATAR AUSTRIA IRAN, ISLAMIC REPUBLIC OF ROMANIA BANGLADESH IRAQ SAUDI ARABIA BELGIUM IRELAND SENEGAL BOLIVIA ISRAEL SIERRA LEONE BRAZIL ITALY SINGAPORE BULGARIA JAMAICA SOUTH AFRICA BYELORUSSIAN SOVIET JAPAN SPAIN SOCIALIST REPUBLIC JORDAN SRI LANKA CAMEROON KENYA SUDAN CANADA KOREA, REPUBLIC OF SWEDEN CHILE KUWAIT SWITZERLAND CHINA LEBANON SYRIAN ARAB REPUBLIC COLOMBIA LIBERIA THAILAND COSTA RICA LIBYAN ARAB JAMAHIRIYA TUNISIA COTE DTVOIRE LIECHTENSTEIN TURKEY CUBA LUXEMBOURG UGANDA CYPRUS MADAGASCAR UKRAINIAN SOVIET SOCIALIST CZECHOSLOVAKIA MALAYSIA REPUBLIC DEMOCRATIC KAMPUCHEA MALI UNION OF SOVIET SOCIALIST DEMOCRATIC PEOPLE'S MAURITIUS REPUBLICS REPUBLIC OF KOREA MEXICO UNITED ARAB EMIRATES DENMARK MONACO UNITED KINGDOM OF GREAT DOMINICAN REPUBLIC MONGOLIA BRITAIN AND NORTHERN ECUADOR MOROCCO IRELAND EGYPT MYANMAR UNITED REPUBLIC OF EL SALVADOR NAMIBIA TANZANIA ETHIOPIA NETHERLANDS UNITED STATES OF AMERICA FINLAND NEW ZEALAND URUGUAY FRANCE NICARAGUA VENEZUELA GABON NIGER VIET NAM GERMANY NIGERIA YUGOSLAVIA GHANA NORWAY ZAIRE GREECE PAKISTAN ZAMBIA GUATEMALA PANAMA ZIMBABWE HAITI PARAGUAY The Agency's Statute was approved on 23 October 1956 by the Conference on the Statute of the IAEA held at United Nations Headquarters, New York; it entered into force on 29 July 1957. The Headquarters of the Agency are situated in Vienna. Its principal objective is "to accelerate and enlarge the contribution of atomic energy to peace, health and prosperity throughout the world". © IAEA, 1991 Permission to reproduce or translate the information contained in this publication may be obtained by writing to the Division of Publications, International Atomic Energy Agency, Wagramerstrasse 5, P.O. Box 100, A-1400 Vienna, Austria. Printed by the IAEA in Austria September 1991 ATOMIC AND PLASMA-MATERIAL INTERACTION DATA FOR FUSION (Supplement to the journal Nuclear Fusion) VOLUME 1 INTERNATIONAL ATOMIC ENERGY AGENCY, VIENNA, 1991 The volumes of ATOMIC AND PLASMA-MATERIAL INTERACTION DATA FOR FUSION are published by the International Atomic Energy Agency as supplements of the journal NUCLEAR FUSION. For these supplements, papers, letters and reviews are accepted which deal with the following topics: — Elementary collision processes in fusion plasmas involving photons, electrons, ions, atoms and molecules; — Collision processes of plasma particles with surfaces of fusion relevant materials; — Plasma-material interaction phenomena, including the thermophysical response of materials. Each submitted contribution should contain fusion relevant data and information in either of the above areas. Original contributions should provide new data, using well established methods. Review articles should give a critical analysis or evaluation of a wider range of data. They are normally prepared on the invitation of the Scientific Editor or on prior mutual consent. Each submitted contribution is assessed by two independent referees. Every manuscript submitted must be accompanied by a disclaimer stating that the paper has not been published and is not being considered for publication elsewhere. If no copyright is claimed by the authors, the IAEA automatically owns the copyright of the paper. Guidelines for the preparation of manuscripts are given on the inside back cover. Manuscripts and correspondence should be addressed to: The Editor, NUCLEAR FUSION, International Atomic Energy Agency, Wagramerstrasse 5, P.O. Box 100, A-1400 Vienna, Austria. Publisher: International Atomic Energy Agency, Wagramerstrasse 5, P.O. Box 100, A-1400 Vienna, Austria Scientific Editor: R.K. Janev, Atomic and Molecular Data Unit, Division of Physical and Chemical Sciences Editor: C. Bobeldijk, Division of Scientific and Technical Information Manuscript Editors: J.W. Weil, Division of Publications Maria Demir, Division of Publications Editorial Board: V.A. Abramov (USSR) A. Miyahara (Japan) R. Behrisch (Germany) R.A. Phaneuf (USA) H.-W. Drawin (France) H.P. Summers (JET) W.B. Gauster (USA) H. Tawara (Japan) Yu.V. Martynenko (USSR) W.L. Wiese (USA) A. Kingston (UK) Annual subscription price (one issue): Austrian Schillings 300,— Airmail delivery (optional): Austrian Schillings 40,— to any destination ATOMIC AND PLASMA-MATERIAL INTERACTION DATA FOR FUSION, VOLUME 1 IAEA, VIENNA, 1991 STI/PUB/23/APID/l FOREWORD Atomic and plasma-wall interaction processes have an important impact on the energy balance, confinement and stability of a thermonuclear plasma. Fusion research areas in which these processes play a prominent part are: plasma radiation losses, impurity control, particle transport, thermal power and helium exhaust, neutral beam plasma heating and fuelling, edge plasma physics and plasma diagnostics. With the progress of fusion research towards the engineering reactor stage, plasma-material interaction processes related to the gross thermophysical response and the thermo- mechanical behaviour of plasma facing components to plasma particle and heat fluxes are also becoming increasingly important. Information on all of these processes is essential for both fusion plasma research and fusion reactor design. The International Atomic Energy Agency, through its Atomic and Molecular Data Unit, co-ordinates a wide spec­ trum of programmes for the compilation, evaluation and generation of atomic, molecular and plasma-material interaction data for fusion. The purpose of these programmes, which were initiated more than fifteen years ago, is to provide the fusion community with consistent and expert assessed information on atomic and plasma-material interaction processes as required in fusion research. Recognizing the need for a more direct exchange of information on these processes between the atomic/material physics community and the fusion community, the Subcommittee on Atomic and Molecular Data for Fusion of the International Fusion Research Council has suggested that the Agency establish an annual publica­ tion on the subject of atomic and plasma-material interaction data for fusion as a supplement to the journal Nuclear Fusion. The content of scientific contributions in this journal-level publication should be strongly data oriented and highly fusion relevant. The contributions should be original in character and should either provide new (or improved) data or evaluate a broader class (or classes) of data or processes (review). While submission of individual contributions corresponding to the scope of the journal is strongly encouraged, it is expected that some contributions will result also from presentations at scientific meetings organized by the Agency in the framework of its co-ordinated data generation and evaluation programmes. The present, first volume of Atomic and Plasma-Material Interaction Data for Fusion contains extended versions of the reviews presented at the IAEA Advisory Group Meeting on Particle-Surface Interaction Data for Fusion, held on 19-21 April 1989 at the IAEA Headquarters in Vienna. The review articles incorporate the original contributions presented at the meeting, as well as the most recent information on the specific subjects covered. The plasma-wall interaction processes considered are the ones which are most important in a reactor level magnetic fusion device and have a strong impact on its operational performance. Apart from the processes induced by particle impact, plasma-material interaction effects related to off-normal plasma events (disruptions, runaway electron bombard­ ment) are covered. A summary of the status of data information for all of these processes from the point of view of fusion reactor design needs is also provided. To a certain extent, this volume can be considered as an updated and complementary source of information to the Data Compendium for Plasma-Surface Interactions published in 1984 as a Special Issue of Nuclear Fusion. Vienna, September 1991 R.K. Janev Scientific Editor CONTENTS R. Behrisch: Particle bombardment and energy fluxes to the vessel walls in controlled thermonuclear fusion devices 7 W. Eckstein: Reflection 17 K.L. Wilson, R. Bastasz, R.A. Causey, D.K. Brice, B.L. Doyle, W.R. Wampler, W. Moller, B.M.U. Scherzer, T. Tanabe: Trapping, detrapping and release of implanted hydrogen isotopes 31 W. Eckstein, J. Bohdansky, J. Roth: Physical sputtering 51 J. Roth, E. Vietzke, A.A. Haasz: Erosion of graphite due to particle impact 63 E.W. Thomas: Particle induced electron emission 79 H. Wolff: Arcing in magnetic fusion devices 93 J.B. Whitley, W.B. Gauster, R.D. Watson, J.A. Koski, A.J. Russo: Pulse heating and effects of disruptions and runaway electrons on first walls and divertors 109 R.K. Janev, A. Miyahara: Plasma-material interaction issues in fusion reactor design and status of the database 123 PARTICLE BOMBARDMENT AND ENERGY FLUXES TO THE VESSEL WALLS IN CONTROLLED THERMONUCLEAR FUSION DEVICES R. BEHRISCH Max-Planck-Institut fur Plasmaphysik, Euratom-IPP Association, Garching bei Munchen, Germany ABSTRACT. For an ignited, continuously
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