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Handbook for Calculations of Nuclear Reaction Data, RIPL-2 Reference Input Parameter Library-2

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Handbook for Calculations of Nuclear Reaction Data, RIPL-2 Reference Input Parameter Library-2 IAEA-TECDOC-1506 Handbook for calculations of nuclear reaction data, RIPL-2 Reference Input Parameter Library-2 Final report of a coordinated research project August 2006 IAEA-TECDOC-1506 Handbook for calculations of nuclear reaction data, RIPL-2 Reference Input Parameter Library-2 Final report of a coordinated research project August 2006 The originating Section of this publication in the IAEA was: Nuclear Data Section International Atomic Energy Agency Wagramer Strasse 5 P.O. Box 100 A-1400 Vienna, Austria HANDBOOK FOR CALCULATIONS OF NUCLEAR REACTION DATA, RIPL-2 IAEA, VIENNA, 2006 IAEA-TECDOC-1506 ISBN 92–0–105206–5 ISSN 1011–4289 © IAEA, 2006 Printed by the IAEA in Austria August 2006 FOREWORD Nuclear data for applications constitute an integral part of the IAEA programme of ac- tivities. When considering low-energy nuclear reactions induced with light particles, such as neutrons, protons, deuterons, alphas and photons, a broad range of applications are addressed, from nuclear power reactors and shielding design through cyclotron production of medical radioisotopes and radiotherapy to transmutation of nuclear waste. All these and many other applications require a detailed knowledge of production cross sections, spectra of emitted particles and their angular distributions. A long-standing problem of how to meet the nuclear data needs of the future with limited experimental resources puts a considerable demand upon nuclear model compu- tation capabilities. Originally, almost all nuclear data were provided by measurement programmes. Over time, theoretical understanding of nuclear phenomena has reached a high degree of reliability, and nuclear modeling has become standard practice in nuclear data evaluations (with measurements remaining critical for data testing and benchmark- ing). Thus, theoretical calculations are instrumental in obtaining complete and internally consistent nuclear data files. The practical use of nuclear model codes requires a considerable numerical input that describes the properties of the nuclei and the interactions involved. Experts have used a variety of different input sets, often developed over years in their own laboratories. Many of these partial input databases were poorly documented or not documented at all, and were not always available for other users. With the trend of reduced funds for nuclear data evaluations, there is a real threat that the immense accumulated knowledge of input parameters and associated calculations may be compromised or even lost for future applications. Therefore, the IAEA has undertaken an extensive co-ordinated effort to develop a library of evaluated and tested nuclear-model input parameters. Considering that such a task is so immense, it was decided to proceed in two major steps. First, to summarize the present knowledge on input parameters and to develop a single Starter File of input model parameters, and then to focus on testing, validating and improving the Starter File. The first step was addressed through the IAEA Co-ordinated Research Project (CRP) entitled “Development of Reference Input Parameter Library for Nuclear Model Calculations of Nuclear Data (Phase I: Starter File)”, initiated in 1994 and completed successfully in 1997. The electronic Starter File (known as RIPL-1) was developed and made available to users throughout the world. The second step followed immediately afterwards within the CRP entitled “Nuclear Model Parameter Testing for Nuclear Data Evaluation (Reference Input Parameter Library: Phase II)”,initiatedin 1998 and completed in 2002. This later CRP resulted in the revision and extension of the original RIPL-1 Starter File to produce a consistent RIPL-2 library containing rec- ommended input parameters, a large amount of theoretical results suitable for nuclear reaction calculations, and a number of computer codes for parameter retrieval, determi- nation and use. The new library will be of immediate practical value for a number of users and should represent a firm basis for future improvements. Initial objectives of the RIPL-2 CRP were: • Test and improve nuclear model parameters for theoretical calculations of nuclear reaction cross sections at incident energies below 100 MeV. • Produce a well-tested Reference Input Parameter Library for calculations of nuclear reactions using nuclear reaction codes. • Develop user-oriented retrieval tools and interfaces to established codes for nuclear reaction calculations. • Publish Technical Report and make the library and tools available on-line and on CD-ROM. The CRP participants (T. Belgya (Hungary), O. Bersillon (France), R. Capote Noy (Cuba), T. Fukahori (Japan), Ge Zhigang (China), S. Goriely (Belgium), M. Herman (IAEA), A. V. Ignatyuk (Russian Federation), S. Kailas (India), A. J. Koning (Nether- lands), P. Obloˇzinsk´y (USA), V. Plujko (Ukraine) and P. G. Young (USA)) convened at three Research Co-ordination Meetings held at: • Vienna, Austria, 25-27 November 1998 (see INDC(NDS)-389, February 1999) • Varenna, Italy, 12-16 June 2000 (see INDC(NDS)-416, September 2000) • Vienna, Austria, 3-7 December 2001 (see INDC(NDS)-431, April 2002) to discuss progress and agree on the contents and form of the new library. In the course of work, the original scope of the CRP has been substantially extended by inclusion of new quantities and results of microscopic calculations for about 8000 nuclei. Extensive efforts have also been dedicated to the testing of the RIPL-2 data. RIPL-2 is targeted at users of nuclear reaction codes interested in low-energy nuclear applications. Incident and outgoing particles include neutrons, protons, deuterons, tri- tons, 3He, 4He and γ, with energies up to approximately 100 MeV. The numerical data and computer codes included in the library are arranged in seven segments/directories: No Directory Contents __ _________ ____________________________________ 1 MASSES Atomic Masses and Deformations 2 LEVELS Discrete Level Schemes 3 RESONANCES Average Neutron Resonance Parameters 4 OPTICAL Optical Model Parameters 5 DENSITIES Level Densities (Total, Partial) 6 GAMMA Gamma-Ray Strength Functions 7 FISSION Fission Barriers and Level Densities The RIPL-2 library is physically located at a Web server operated by the IAEA, and can be conveniently accessed by pointing any Web browser at: http://www-nds.iaea.org/RIPL-2/ This Web site provides for downloading entire RIPL-2 segments, individual files, and retrieval of selected data. In addition, some basic calculations and graphical comparisons of parameters are also available. A CD-ROM with the complete RIPL-2 library can be requested cost-free from the IAEA. This Handbook contains a full description of the library including the physics involved, with an introductory and seven technical chapters, plus related Annexes that describe the library structure as defined above. During the development of RIPL-2, several important issues could not be addressed within the current CRP. Therefore, a third phase of the RIPL project has been initiated in 2002 in order to extend the applicability of the library to cross sections for reactions on nuclei far from the stability line, incident energies beyond 100 MeV, and reactions induced by charged particles. This phase is planned for completion in 2006-07. The IAEA wishes to thank all participants of the CRP for their diligent work that has lead to the creation of the Reference Input Parameter Library, and for their valu- able contributions to the present Technical Report. Finally, M. Herman was the IAEA responsible officer for the CRP, this publication and the resulting database. EDITORIAL NOTE The use of particular designations of countries or territories does not imply any judgement by the publisher, the IAEA, as to the legal status of such countries or territories, of their authorities and institutions or of the delimitation of their boundaries. The mention of names of specific companies or products (whether or not indicated as registered) does not imply any intention to infringe proprietary rights, nor should it be construed as an endorsement or recommendation on the part of the IAEA. Contributing Authors T. Belgya (Institute of Isotope and Surface Chemistry, Hungary) O. Bersillon (Centre d’Etudes Nucleaires de Bruyeres-le-Chatel, France) R. Capote Noy (Centro de Estudios Aplicados al Desarrollo Nuclear, Cuba) T. Fukahori (Japan Atomic Energy Agency, Japan) Ge Zhigang (China Institute of Atomic Energy, China) S. Goriely (Universite Libre de Bruxelles, Belgium) M. Herman (International Atomic Energy Agency) A.V. Ignatyuk (Institute of r Physics and Power Engineering, Russian Federation) S. Kailas (Bhabha Atomic Research Centre, India) A.J. Koning (Nuclear Research and Consultancy Group, Netherlands) P. Obloˇzinsk´y (Brookhaven National Laboratory, USA) V. Plujko (Taras Shevchenko National University, Ukraine) P.G. Young (Los Alamos National Laboratory, USA) Contents 1 Introduction 1 2 Atomic Masses 5 2.1Atomicmasses................................. 5 2.1.1 Experimentalmasses.......................... 6 2.1.2 Finite-Range-Droplet-Modelmasstable................ 6 2.1.3 Hartree-Fock-Bogoliubovmasstable................. 6 2.1.4 Duflo-Zuker approximation to the Shell Model . 7 2.2Shellcorrections................................. 8 2.3Deformations.................................. 9 2.4 Relative isotopic abundances . 9 2.5Summaryofcodesanddatafiles........................ 9 3 Discrete Levels 11 3.1DiscreteLevelSchemeLibrary(DLSL).................... 12 3.1.1 FormatoftheDiscreteLevelSchemesLibrary............ 14
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