1- TOPIC: 292001 KNOWLEDGE: K1.02 [3.0/3.1] QID: B45 the Term “Neutron Generation Time” Is Defined As the Average Time Betw
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Spent Nuclear Fuel Pools in the US
Spent Nuclear Fuel Pools in the U.S.: Reducing the Deadly Risks of Storage front cover WITH SUPPORT FROM: WITH SUPPORT FROM: By Robert Alvarez 1112 16th St. NW, Suite 600, Washington DC 20036 - www.ips-dc.org May 2011 About the Author Robert Alvarez, an Institute for Policy Studies senior scholar, served as a Senior Policy Advisor to the Secre- tary of Energy during the Clinton administration. Institute for Policy Studies (IPS-DC.org) is a community of public scholars and organizers linking peace, justice, and the environment in the U.S. and globally. We work with social movements to promote true democracy and challenge concentrated wealth, corporate influence, and military power. Project On Government Oversight (POGO.org) was founded in 1981 as an independent nonprofit that investigates and exposes corruption and other misconduct in order to achieve a more effective, accountable, open, and ethical federal government. Institute for Policy Studies 1112 16th St. NW, Suite 600 Washington, DC 20036 http://www.ips-dc.org © 2011 Institute for Policy Studies [email protected] For additional copies of this report, see www.ips-dc.org Table of Contents Summary ...............................................................................................................................1 Introduction ..........................................................................................................................4 Figure 1: Explosion Sequence at Reactor No. 3 ........................................................4 Figure 2: Reactor No. 3 -
KINETIC ANALYSIS of SUB-PROMPT-CRITICAL REACTOR ASSEMBLIES Hy S Das Theoretical Physics Division
BARC/1992/E/011 O 1 "o KINETIC ANALYSIS OF SUB-PROMPT-CRITICAL REACTOR ASSEMBLIES hy S Das Theoretical Physics Division 1992 BARC/1992/E/011 o UJ GOVERNMENT OF INDIA - AATOMIT C ENERGY COMMISSION U KINETIC ANALYSIS OF SUB-PROMPT-CRITICAL REACTOR ASSEMBLIES by S. Das Theoretical Physics Division BHABHA ATOMIC RESEARCH CENTRE BOMBAY, INDIA 1992 BARC/1992/E/011 BIBLIOBRAPHIC DESCRIPTION SHEET FOR TECHNICAL REPORT (as par IS i 94BNB - 1980) 01 Security classification i Unclassified 02 Distribution t External 03 Report status i New 04 Series i BARC External 05 Report type i Technical Report 06 Report No. i BARC/1992/E/011 07 Part No. or Volume No. i 08 Contract No. i 10 Title and subtitle i Kinetic analysis of sub-prompt- critical reactor assemblies 11 Collation i 14 p.f 4 figs., 1 tab. IS Project No. i 20 Personal author<s> i S. Das 21 Affiliation of author(s) i Theoretical Physics Division, Bhabha Atomic Research Centre, Bombay 22 Corporate author(s) i Bhabha Atomic Research Centre, Bombay - 400 085 23 Originating unit i Theoretical Physics Division, BARC, Bombay 24 Sponsor(s) Name i Department of Atomic Energy Type i Government 30 Date of submission i May 1992 31 Publication/Issue date i June 1992 Contd... (ii) 1 40 Publ i»h»r/Distributor t Head, Library and Information Division, Bhabha Atomic Rasaarch Contra, Bombay 42 Form of distribution t Hard Copy 50 Languaga of taxt i English 51 Languaga o-f summary i English 92 No. of references i % rafs. 53 Givas data on i 60 Abstract x Nautronic analysis of safaty-ralatad kinetics problams in experimental neutron multiplying assemblies has bean carried out using a sub-prompt-critical reactor model. -
Progress in Fusion-Driven Transmutation Research in China
Progress in Fusion-Driven Transmutation Research in China Yican WU Institute of Plasma Physics, Chinese Academy of Sciences P.O. Box 1126, Hefei, Anhui, 230031, China E-mail: [email protected] Fax: +86 551 5591310 1. Introduction Although the recent experiments and associated theoretical studies of fusion energy development have proven the feasibility of fusion power, it's commonly realized that it needs hard work before pure fusion energy could commercially and economically utilized. On the other hand, the fission nuclear industry has been falling on hard times recently since so far there has been no conclusion about how to deal with the long-lived wastes produced from the nuclear spent fuel and about how to solve the shortage of natural uranium ore in addition to nuclear safety and proliferation. It's a natural way to develop fusion-fission hybrid reactors including fuel producing reactors and waste transmuting reactors as an alternate strategy to speed up the time for producing energy since a hybrid reactor as a subcritical system can operate with lower fusion energy gain ratios Q, therefore the design of the fusion core for a hybrid system is easier than for a pure fusion reactor. The fusion-fission hybrid concept dates back to the earliest days of the fusion project when it was recognized that using fusion neutrons to breed nuclear fuel would vastly increase the energy from fusion plant. It appears to receive almost no attention since the mid 80's in the world, except in China who has given very serious consideration and has strong hybrid reactor activities since 1986 in the framework of the National Hi’Tech Program supported by the State Science and Technology Commission (SSTC) of China. -
PGNAA Neutron Source Moderation Setup Optimization
Submitted to ‘Chinese Physics C PGNAA neutron source moderation setup optimization Zhang Jinzhao1（张金钊）Tuo Xianguo1（庹先国） (1.Chengdu University of Technology Applied Nuclear Techniques in Geoscience Key Laboratory of Sichuan Province，Chengdu 610059，China) Abstract: Monte Carlo simulations were carried out to design a prompt γ-ray neutron activation analysis (PGNAA) thermal neutron output setup using MCNP5 computer code. In these simulations the moderator materials, reflective materials and structure of the PGNAA 252Cf neutrons of thermal neutron output setup were optimized. Results of the calcuations revealed that the thin layer paraffin and the thick layer of heavy water moderated effect is best for 252Cf neutrons spectrum. The new design compared with the conventional neutron source design, the thermal neutron flux and rate were increased by 3.02 times and 3.27 times. Results indicate that the use of this design should increase the neutron flux of prompt gamma-ray neutron activation analysis significantly. Key word: PGNAA; neutron source; thermal neutron; moderation; reflection 1. Introduction study, Monte Carlo calculation was carried out for the Prompt gamma ray neutron activation analysis design of a 252Cf neutron source moderation setup for the (PGNAA) is a rapid, nondestructive, powerful analysis cement samples[7]. The model of Monte Carlo multielemental analysis technique, large samples of some simulation was verified by experiment[8, 9].We improve minor, trace light elements and is used in industrial the thermal neutron source yield rate of 252Cf neutron by control[1-5]. In a PGNAA analysis, the sample nuclear the PGNAA neutron source structure to the design. The composition is determined from prompt gamma rays calculation results for the new design were compared which produced through neutron inelastic scattering and with the previous, example: themal neutron flux rate, fast thermal neutron capture. -
Nuclear Weapons Technology 101 for Policy Wonks Bruce T
NUCLEAR WEAPONS TECHNOLOGY FOR POLICY WONKS NUCLEAR WEAPONS TECHNOLOGY 101 FOR POLICY WONKS BRUCE T. GOODWIN BRUCE T. GOODWIN BRUCE T. Center for Global Security Research Lawrence Livermore National Laboratory August 2021 NUCLEAR WEAPONS TECHNOLOGY 101 FOR POLICY WONKS BRUCE T. GOODWIN Center for Global Security Research Lawrence Livermore National Laboratory August 2021 NUCLEAR WEAPONS TECHNOLOGY 101 FOR POLICY WONKS | 1 This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory in part under Contract W-7405-Eng-48 and in part under Contract DE-AC52-07NA27344. The views and opinions of the author expressed herein do not necessarily state or reflect those of the United States government or Lawrence Livermore National Security, LLC. ISBN-978-1-952565-11-3 LCCN-2021907474 LLNL-MI-823628 TID-61681 2 | BRUCE T. GOODWIN Table of Contents About the Author. 2 Introduction . .3 The Revolution in Physics That Led to the Bomb . 4 The Nuclear Arms Race Begins. 6 Fission and Fusion are "Natural" Processes . 7 The Basics of the Operation of Nuclear Explosives. 8 The Atom . .9 Isotopes . .9 Half-life . 10 Fission . 10 Chain Reaction . 11 Critical Mass . 11 Fusion . 14 Types of Nuclear Weapons . 16 Finally, How Nuclear Weapons Work . 19 Fission Explosives . 19 Fusion Explosives . 22 Staged Thermonuclear Explosives: the H-bomb . 23 The Modern, Miniature Hydrogen Bomb . 25 Intrinsically Safe Nuclear Weapons . 32 Underground Testing . 35 The End of Nuclear Testing and the Advent of Science-Based Stockpile Stewardship . 39 Stockpile Stewardship Today . 41 Appendix 1: The Nuclear Weapons Complex . -
Total Prompt Energy Release in the Neutron-Induced Fission Of
Nuclear Physics A 772 (2006) 113–137 Total prompt energy release in the neutron-induced fission of 235U, 238U, and 239Pu D.G. Madland Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA Received 12 January 2006; received in revised form 28 March 2006; accepted 29 March 2006 Available online 2 May 2006 Abstract This study addresses, for the first time, the total prompt energy release and its components for the fission of 235U, 238U, and 239Pu as a function of the kinetic energy of the neutron inducing the fission. The com- ponents are extracted from experimental measurements, where they exist, together with model-dependent calculation, interpolation, and extrapolation. While the components display clear dependencies upon the incident neutron energy, their sums display only weak, yet definite, energy dependencies. Also addressed is the total prompt energy deposition in fission for the same three systems. Results are presented in equation form. New measurements are recommended as a consequence of this study. © 2006 Elsevier B.V. All rights reserved. PACS: 24.75.+i; 25.85.Ec; 25.85.Ca; 27.90.+b Keywords: Energy release and energy deposition in neutron-induced fission; Experiment and Los Alamos model; 235U; 238U; 239Pu 1. Introduction This study is a consequence of open questions on the magnitudes of the total prompt energy re- lease in fission, the total prompt energy deposition in fission, the components of these quantities, and their dependencies upon the kinetic energy of the neutron inducing the fission. Our results are given in Eqs. (31)–(33) and Fig. 17 for the total prompt energy release in fission, and in Eqs. -
Fundamentals of Nuclear Power
Fundamentals of Nuclear Power Juan S. Giraldo Douglas J. Gotham David G. Nderitu Paul V. Preckel Darla J. Mize State Utility Forecasting Group December 2012 Table of Contents List of Figures .................................................................................................................................. iii List of Tables ................................................................................................................................... iv Acronyms and Abbreviations ........................................................................................................... v Glossary ........................................................................................................................................... vi Foreword ........................................................................................................................................ vii 1. Overview ............................................................................................................................. 1 1.1 Current state of nuclear power generation in the U.S. ......................................... 1 1.2 Nuclear power around the world ........................................................................... 4 2. Nuclear Energy .................................................................................................................... 9 2.1 How nuclear power plants generate electricity ..................................................... 9 2.2 Radioactive decay ................................................................................................. -
Behaviour of Neutron Moderator Materials at High Temperatures in CASTOR®-Casks: Qualification and Assessment
14th International Symposium on the Packaging and Paper # 235 Transportation of Radioactive Materials (PATRAM 2004), Berlin, Germany, September 20-24, 2004 Behaviour of Neutron Moderator Materials at High Temperatures in CASTOR®-Casks: Qualification and Assessment Torsten Krietsch1), Dietmar Wolff1), Ulrich Knopp2) and Hans-Dieter Brocke3) 1) Federal Institute for Materials Research and Testing (BAM), Berlin, Germany 2) Gesellschaft für Nuklear-Behälter mbH (GNB), Essen, Germany 3) TÜV Rheinland Group, Berlin, Germany 1. Introduction The Federal Institute for Materials Research and Testing (BAM) is the responsible German authority for the assessment of mechanical and thermal designs of transport and storage casks for radioactive materials. BAM checks up the proofs of the applicants in their safety reports and assesses the conformity to the Regulations for the Safe Transport of Radioactive Material [1, 2]. One applicant is the Gesellschaft für Nuklear-Behälter mbH (GNB) with a new generation of transport and storage casks of CASTOR®-design. GNB typically uses ultra high molecular weight Polyethylene (UHMW-PE) for the moderation of free neutrons. Rods made of UHMW-PE are positioned in axial bore holes in the wall of the cask and plates of UHMW-PE are in free spaces between primary and secondary lid and between the bottom of the cask and an outer plate (Figure 1). Because of the heat generated by the radioactive inventory and because of a strained spring at the bottom of every bore hole, UHMW- PE is subjected to permanent thermal and mechanical loads as well as loads from gamma and neutron radiation. UHMW-PE has been used under routine- and normal conditions of transport for maximum temperatures up to 130 °C. -
Systematic of Delayed Neutron Parameters
RU0110988 40 XIV International Workshop on Nuclear Fission Physics Systematic of Delayed Neutron Parameters S.G. Isaev, V.M. Piksaikin Institute of Physics and Power Engineering, Obninsk, Russia Abstract The experimental studies of the energy dependence of the delayed neutron parameters for various fissioning systems has shown that the behavior of a some combination of delayed neutron parameters has a similar features. On the basis of this findings the systematics of delayed neutron experimental data for thorium, uranium, plutonium and americium isotopes have been investigated with the purpose to find a correlation of DN parameters with characteristics of fissioning system as well as a correlation between the delayed neutron parameters themselves. Below we will present the preliminary results which were obtained during this study omitting the physics interpretation of the results. Introduction The knowledge of the time dependence of P-delayed neutron emission is of great importance for the development of reliable data base required both for reactor-physics analysis and for the investigation of nuclei which are far from the valley of stability. Since discovery of delayed neutrons the time dependence of delayed neutron emission from neutron induced fission was studied in more than 238 experiments [1]. In parallel to the experimental studies of aggregate DN emission from neutron induced fission the group parameters of delayed neutron emission were calculated using microscopic approach (summation technique) [2]. These calculations are based on the knowledge of the emission probabilities values Pn, half-life values and yields of individual precursors of delayed neutrons [3]. One of the main results of the aggregate DN decay curve measurements was that the group periods (or decay constants) for various fissioning systems for fast neutrons induced fission do not differ from each other [4]. -
Radiation Detection from Fission
ORNL/TM-2004/234 RADIATION DETECTION FROM FISSION J. T. Mihalczo DOCUMENT AVAILABILITY Reports produced after January 1, 1996, are generally available free via the U.S. Department of Energy (DOE) Information Bridge. Web site http://www.osti.gov/bridge Reports produced before January 1, 1996, may be purchased by members of the public from the following source. National Technical Information Service 5285 Port Royal Road Springfield, VA 22161 Telephone 703-605-6000 (1-800-553-6847) TDD 703-487-4639 Fax 703-605-6900 E-mail [email protected] Web site http://www.ntis.gov/support/ordernowabout.htm Reports are available to DOE employees, DOE contractors, Energy Technology Data Exchange (ETDE) representatives, and International Nuclear Information System (INIS) representatives from the following source. Office of Scientific and Technical Information P.O. Box 62 Oak Ridge, TN 37831 Telephone 865-576-8401 Fax 865-576-5728 E-mail [email protected] Web site http://www.osti.gov/contact.html This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. -
Integrated Waste Assay System (Iwas) and Analysis Enhancements
WM’05 Conference, February 27 - March 3, 2005, Tucson, AZ INTEGRATED WASTE ASSAY SYSTEM (IWAS) AND ANALYSIS ENHANCEMENTS R.D. McElroy, Jr. and S. Croft Canberra Industries, Inc. ABSTRACT The Integrated Waste Assay System (IWAS) is a hybrid waste assay system developed to provide high throughput and improved data quality for characterization of transuranic wastes contained within 200 liter drums and 320 liter overpacks. The IWAS combines high efficiency passive neutron coincidence counting, active neutron interrogation and high resolution gamma-ray spectroscopy into a single assay cavity. The complementary nature of the multiple assay modes yields a higher success rate than any single assay mode alone allowing the system to accommodate a wide range of source and matrix types. Performance of the individual assay modes and performance of the combined analyses is discussed. Modifications and enhancements of the traditional analysis algorithms for the passive and active neutron analyses were implemented in the IWAS. Reductions of the passive neutron detection levels of up to 50% have been achieved without the need to increase the neutron detection efficiency. Utilization of the Add-A- Source matrix correction measurement for determination of the active interrogation moderator index provided a means to implement a moderator correction for low Pu mass samples and uranium only samples. The modified algorithms and performance improvements are discussed. The IWAS analysis makes use of data obtained from the three assay modalities to identify and flag problem waste drums. The analysis makes use of the Total Measurement Uncertainty (TMU) analysis for each assay modality to identify the mode providing the result that most likely represents the actual drum contents. -
Nuclear Fission Dynamics: Past, Present, Needs, and Future
NT@UW-19-18,LA-UR-19-32211 Nuclear Fission Dynamics: Past, Present, Needs, and Future Aurel Bulgac,1 Shi Jin,1 and Ionel Stetcu2 1Department of Physics, University of Washington, Seattle, Washington 98195–1560, USA 2Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA (Dated: March 23, 2020) Significant progress in the understanding of the fission process within a microscopic framework has been recently reported. Even though the complete description of this important nuclear reac- tion remains a computationally demanding task, recent developments in theoretical modeling and computational power have brought current microscopic simulations to the point where they can pro- vide guidance and constraints to phenomenological models, without making recourse to parameters. An accurate treatment compatible with our understanding of the inter-nucleon interactions should be able to describe the real-time dynamics of the fissioning system and could justify or rule out assumptions and approximations incompatible with the underlying universally accepted quantum- mechanical framework. Of particular importance are applications to observables that cannot be directly measured in experimental setups (such as the angular momentum distribution of the fission fragments, or the excitation energy sharing between the fission fragments, or fission of nuclei formed during the r-process), and their dependence of the excitation energy in the fissioning system. Even if accurate predictions are not within reach, being able to extract the trends with increasing exci- tation energy is important in various applications. The most advanced microscopic simulations of the fission process do not support the widely used assumption of adiabaticity of the large amplitude collective motion in fission, in particular for trajectories from the outer saddle towards the scission configuration.