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Compilation and Evaluation of Fission Yield Nuclear Data Iaea, Vienna, 2000 Iaea-Tecdoc-1168 Issn 1011–4289
IAEA-TECDOC-1168 Compilation and evaluation of fission yield nuclear data Final report of a co-ordinated research project 1991–1996 December 2000 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 COMPILATION AND EVALUATION OF FISSION YIELD NUCLEAR DATA IAEA, VIENNA, 2000 IAEA-TECDOC-1168 ISSN 1011–4289 © IAEA, 2000 Printed by the IAEA in Austria December 2000 FOREWORD Fission product yields are required at several stages of the nuclear fuel cycle and are therefore included in all large international data files for reactor calculations and related applications. Such files are maintained and disseminated by the Nuclear Data Section of the IAEA as a member of an international data centres network. Users of these data are from the fields of reactor design and operation, waste management and nuclear materials safeguards, all of which are essential parts of the IAEA programme. In the 1980s, the number of measured fission yields increased so drastically that the manpower available for evaluating them to meet specific user needs was insufficient. To cope with this task, it was concluded in several meetings on fission product nuclear data, some of them convened by the IAEA, that international co-operation was required, and an IAEA co-ordinated research project (CRP) was recommended. This recommendation was endorsed by the International Nuclear Data Committee, an advisory body for the nuclear data programme of the IAEA. As a consequence, the CRP on the Compilation and Evaluation of Fission Yield Nuclear Data was initiated in 1991, after its scope, objectives and tasks had been defined by a preparatory meeting. -
VII. Nuclear Fission and Fusion Lorant Csige
VII.VII. NuclearNuclear FissionFission andand FusionFusion LorantLorant CsigeCsige LaboratoryLaboratory forfor NuclearNuclear PhysicsPhysics HungarianHungarian AcademyAcademy ofof SciencesSciences NuclearNuclear bindingbinding energy:energy: possibilitypossibility ofof energyenergy productionproduction NuclearNuclear FusionFusion ● Some basic principles: ─ two light nuclei should be very close to defeat the Coulomb repulsion → nuclear attraction: kinetic energy!! ─ not spontenious, difficult to achieve in reality ─ advantage: large amount of hydrogen and helium + solutions without producing any readioactive product NuclearNuclear fusionfusion inin starsstars ● proton-proton cycle: ~ mass of Sun, many branches ─ 2 + ν first step in all branches (Q=1.442 MeV): p+p → H+e +νe ● diproton formation (and immediate decay back to two protons) is the ruling process ● stable diproton is not existing → proton – proton fusion with instant beta decay! ● very slow process since weak interaction plays role → cross section has not yet been measrued experimentally (one proton „waits” 9 billion years to fuse) ─ second step: 2H+1H → 3He + γ + 5.49 MeV ● very fast process: only 4 seconds on the avarage ● 3He than fuse to produce 4He with three (four) differenct reactions (branches) ─ ppI branch: 3He + 3He → 4He + 1H + 1H + 12.86 MeV ─ ppII branch: ● 3He + 4He → 7Be + γ 7 7 ● 7 7 ν Be + e- → Li + νe ● 7Li + 1H → 4He + 4He ─ ppIII branch: only 0.11% energy of Sun, but source of neutrino problem ● 3He + 4He → 7Be + γ 7 1 8 8 + 4 4 ● 7 1 8 γ 8 + ν 4 4 Be + H → -
Spontaneous Fission
13) Nuclear fission (1) Remind! Nuclear binding energy Nuclear binding energy per nucleon V - Sum of the masses of nucleons is bigger than the e M / nucleus of an atom n o e l - Difference: nuclear binding energy c u n r e p - Energy can be gained by fusion of light elements y g r e or fission of heavy elements n e g n i d n i B Mass number 157 13) Nuclear fission (2) Spontaneous fission - heavy nuclei are instable for spontaneous fission - according to calculations this should be valid for all nuclei with A > 46 (Pd !!!!) - practically, a high energy barrier prevents the lighter elements from fission - spontaneous fission is observed for elements heavier than actinium - partial half-lifes for 238U: 4,47 x 109 a (α-decay) 9 x 1015 a (spontaneous fission) - Sponatenous fission of uranium is practically the only natural source for technetium - contribution increases with very heavy elements (99% with 254Cf) 158 1 13) Nuclear fission (3) Potential energy of a nucleus as function of the deformation (A, B = energy barriers which represent fission barriers Saddle point - transition state of a nucleus is determined by its deformation - almost no deformation in the ground state - fission barrier is higher by 6 MeV Ground state Point of - tunneling of the barrier at spontaneous fission fission y g r e n e l a i t n e t o P 159 13) Nuclear fission (4) Artificially initiated fission - initiated by the bombardment with slow (thermal neutrons) - as chain reaction discovered in 1938 by Hahn, Meitner and Strassmann - intermediate is a strongly deformed -
22.101 Applied Nuclear Physics (Fall 2006) Problem Set No. 1 Due: Sept
22.101 Applied Nuclear Physics (Fall 2006) Problem Set No. 1 Due: Sept. 13, 2006 Problem 1 Before getting into the concepts of nuclear physics, every student should have some feeling for the numerical values of properties of nuclear radiations, such as energy and speed, wavelength, and frequency, etc. This involves some back of the envelope calculations using appropriate universal constants. (i) A thermal neutron in a nuclear reactor is a neutron with kinetic energy equal to kBT, where kB is the Boltzmann’s constant and T is the temperature of the reactor. Explain briefly the physical basis of this statement. Taking T to be the room temperature, 20C, calculate the energy of the thermal neutron (in units of ev), and then find its speed v (in cm/sec), the de Broglie wavelength λ (in A) and circular frequency ω (radian/sec). Compare these values with the energy, speed, and interatomic distance of atoms that make up the materials in the reactor. What is the point of comparing the neutron wavelength with typical atomic separations in a solid? (ii) Consider a 2 Kev x-ray, calculate the frequency and wavelength of this photon. What would be the point of comparing the x-ray wavelength with that of the thermal neutron? For an electron with wavelength equal to that of the thermal neutron, what energy would it have? 2 2 (iii) The classical radius of the electron, defined as e / mec , with e being the electron charge, me the electron rest mass, and c the speed of light, has the value of 2.818 x 10-13 cm. -
Problem Set 3 Solutions
22.01 Fall 2016, Problem Set 3 Solutions October 9, 2016 Complete all the assigned problems, and do make sure to show your intermediate work. 1 Activity and Half Lives 1. Given the half lives and modern-day abundances of the three natural isotopes of uranium, calculate the isotopic fractions of uranium when the Earth first formed 4.5 billion years ago. Today, uranium consists of 0.72% 235U, 99.2745% 238U, and 0.0055% 234U. However, it is clear that the half life of 234U (245,500 years) is so short compared to the lifetime of the Earth (4,500,000,000 years) that it would have all decayed away had there been some during the birth of the Earth. Therefore, we look a little closer, and find that 234U is an indirect decay product of 238U, by tracing it back from its parent nuclides on the KAERI table: α β− β− 238U −! 234T h −! 234P a −! 234U (1) Therefore we won’t consider there being any more 234U than would normally be in equi librium with the 238U around at the time. We set up the two remaining equations as follows: −t t ;235 −t t ;238 = 1=2 = 1=2 N235 = N0235 e N238 = N0238 e (2) Using the current isotopic abundances from above as N235 and N238 , the half lives from n 9 t 1 1 the KAERI Table of Nuclides t =2;235 = 703800000 y; t =2;238 = 4:468 · 10 y , and the lifetime of the earth in years (keeping everything in the same units), we arrive at the following expressions for N0235 and N0238 : N235 0:0072 N238 0:992745 N0235 =−t = 9 = 4:307N0238 =−t = 9 = 2:718 (3) =t1 ;235 −4:5·10 =7:038·108 =t1 ;238 −4:5·10 =4:468·109 e =2 e e =2 e Finally, taking the ratios of these two relative abundances gives us absolute abundances: 4:307 2:718 f235 = = 0:613 f238 = = 0:387 (4) 4:307 + 2:718 4:307 + 2:718 235U was 61.3% abundant, and 238U was 38.7% abundant. -
Low-Energy Nuclear Physics Part 2: Low-Energy Nuclear Physics
BNL-113453-2017-JA White paper on nuclear astrophysics and low-energy nuclear physics Part 2: Low-energy nuclear physics Mark A. Riley, Charlotte Elster, Joe Carlson, Michael P. Carpenter, Richard Casten, Paul Fallon, Alexandra Gade, Carl Gross, Gaute Hagen, Anna C. Hayes, Douglas W. Higinbotham, Calvin R. Howell, Charles J. Horowitz, Kate L. Jones, Filip G. Kondev, Suzanne Lapi, Augusto Macchiavelli, Elizabeth A. McCutchen, Joe Natowitz, Witold Nazarewicz, Thomas Papenbrock, Sanjay Reddy, Martin J. Savage, Guy Savard, Bradley M. Sherrill, Lee G. Sobotka, Mark A. Stoyer, M. Betty Tsang, Kai Vetter, Ingo Wiedenhoever, Alan H. Wuosmaa, Sherry Yennello Submitted to Progress in Particle and Nuclear Physics January 13, 2017 National Nuclear Data Center Brookhaven National Laboratory U.S. Department of Energy USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26) Notice: This manuscript has been authored by employees of Brookhaven Science Associates, LLC under Contract No.DE-SC0012704 with the U.S. Department of Energy. The publisher by accepting the manuscript for publication acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. DISCLAIMER 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, nor any of their contractors, subcontractors, or their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or any third party’s use or the results of such use of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. -
Measuring the Fission Barrier of 254No Gregoire Henning
Stability of Transfermium Elements at High Spin : Measuring the Fission Barrier of 254No Gregoire Henning To cite this version: Gregoire Henning. Stability of Transfermium Elements at High Spin : Measuring the Fission Bar- rier of 254No. Other [cond-mat.other]. Université Paris Sud - Paris XI, 2012. English. NNT : 2012PA112143. tel-00745915 HAL Id: tel-00745915 https://tel.archives-ouvertes.fr/tel-00745915 Submitted on 26 Oct 2012 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés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bstract Super heavy nuclei provide opportunities to study nuclear struc- ture near three simultaneous limits: in charge Z, spin I and excita- tion energy E∗. -
American Chemical Society Division of Nuclear Chemistry and Technology 247Th ACS National Meeting, Dallas, TX, March 16-20, 2014
American Chemical Society Division of Nuclear Chemistry and Technology 247th ACS National Meeting, Dallas, TX, March 16-20, 2014 J. Braley, Program Chair; P. Mantica, Program Chair SUNDAY MORNING Glenn T. Seaborg Award for Nuclear Chemistry: Symposium in Honor of Walter D. Loveland D. Morrissey, Organizer; D. Thomas, Organizer; D. Morrissey, Presiding Papers 1-5 SUNDAY AFTERNOON Radiation Hardened Materials for Accelerators, Reactors and Spacecraft R. Devanathan, Organizer; I. Szlufarska, Presiding; R. Devanathan, Presiding Papers 6- 11 Glenn T. Seaborg Award for Nuclear Chemistry: Symposium in Honor of Walter D. Loveland D. Thomas, Organizer; D. Morrissey, Organizer; J. Natowitz, Presiding Papers 12-16 MONDAY MORNING Glenn T. Seaborg Award for Nuclear Chemistry: Symposium in Honor of Walter D. Loveland D. Thomas, Organizer; D. Morrissey, Organizer; C. Folden, Presiding Papers 22-26 Radiation Hardened Materials for Accelerators, Reactors and Spacecraft R. Devanathan, Organizer; K. Nordlund, Presiding Papers 17-21 MONDAY AFTERNOON Symposium in Honor of Norman Edelstein: A Distinguished and Diverse Scientific Career in Actinide Chemistry A. Sattelberger, Organizer; D. Clark, Organizer; D. Shuh, Organizer; L. Soderholm, Organizer; D. Clark, Presiding Papers 32-40 Radiation Hardened Materials for Accelerators, Reactors and Spacecraft R. Devanathan, Organizer; J. Greer, Presiding Papers 27-31 TUESDAY MORNING Global Status of Nuclear Energy J. Terry, Organizer; K. Nash, Organizer; J. Terry, Presiding; K. Nash, Presiding Papers 41-48 Symposium in Honor of Norman Edelstein: A Distinguished and Diverse Scientific Career in Actinide Chemistry A. Sattelberger, Organizer; D. Clark, Organizer; D. Shuh, Organizer; L. Soderholm, Organizer; J. Gibson, Presiding Papers 49-59 TUESDAY AFTERNOON Global Status of Nuclear Energy K. -
Large-Scale Calculation of Fission Barrier Parameters for 5254 Nuclei with 171 ≤ a ≤ 330
Nuclear Physcs Large-Scale Calculation of Fission Barrier Parameters for 5254 Nuclei with 171 ≤ A ≤ 330 Peter Möller, Arnold J. Sierk, T-16 n previous Theoretical Division Nuclear the calculated potential-energy surfaces. At Weapons Highlights issues, we have this stage we have extracted the heights of discussed calculations of fission the first and second barrier peaks and the potential-energy surfaces as functions fission-isomeric state for all 5254 nuclei. Iof up to five different nuclear shape coordinates as the system evolves from a Figure 1 shows a comparison between ground-state shape to two separated fission calculated and experimental barrier fragments. The five shape coordinates we parameters for a sequence of uranium consider beyond the second minimum in the nuclei. The experimental data are from a fission barrier (fission isomer) are elongation, review by Madland [1]. Sometimes the neck radius, spheroidal deformations of the results of several experiments are plotted for emerging left and right fragments, and left- the same isotope. We have made such right mass asymmetry. For less deformed comparisons for isotope chains of all shapes between the spherical shape and the elements from Th to Es (Z = 90 to Z = 99). second minimum in the barrier we consider Such detailed knowledge about the barrier three shape coordinates in the Nilsson structure and other nuclear structure ε ε perturbed-spheroid parameterization: 2 properties are necessary to model (n,f), ε γ (quadrupole), 4 (hexadecapole), and (axial (n,2n), and many other cross -
The Jules Horowitz Reactor Research Project
EPJ Web of Conferences 115, 01003 (2016) DOI: 10.1051/epjconf/201611501003 © Owned by the authors, published by EDP Sciences, 2016 nd 2 Int. Workshop Irradiation of Nuclear Materials: Flux and Dose Effects November 4-6, 2015, CEA – INSTN Cadarache, France The Jules Horowitz Reactor Research Project: A New High Performance Material Testing Reactor Working as an International User Facility – First Developments to Address R&D on Material Gilles BIGNAN1, Christian COLIN1, Jocelyn PIERRE1, Christophe BLANDIN1, Christian GONNIER1, Michel AUCLAIR2, Franck ROZENBLUM2 1 CEA-DEN-DER, JHR Project (Cadarache, France) 2 CEA-DEN-DRSN, Service d'Irradiations en Réacteurs et d'Etudes Nucléaires, SIREN (Saclay, France) The Jules Horowitz Reactor (JHR) is a new Material Testing Reactor (MTR) currently under construction at CEA Cadarache research center in the south of France. It will represent a major research infrastructure for scientific studies dealing with material and fuel behavior under irradiation (and is consequently identified for this purpose within various European road maps and forums; ESFRI, SNETP…). The reactor will also contribute to medical Isotope production. The reactor will perform R&D programs for the optimization of the present generation of Nuclear Power Plans (NPPs), will support the development of the next generation of NPPs (mainly LWRs) and also will offer irradiation capabilities for future reactor materials and fuels. JHR is fully optimized for testing material and fuel under irradiation, in normal, incidental and accidental situations: with modern irradiation loops producing the operational condition of the different power reactor technologies ; with major innovative embarked in-pile instrumentation and out-pile analysis to perform high- quality R&D experiments ; with high thermal and fast neutron flux capacity and high dpa rate to address existing and future NPP needs. -
Module01 Nuclear Physics and Reactor Theory
Module I Nuclear physics and reactor theory International Atomic Energy Agency, May 2015 v1.0 Background In 1991, the General Conference (GC) in its resolution RES/552 requested the Director General to prepare 'a comprehensive proposal for education and training in both radiation protection and in nuclear safety' for consideration by the following GC in 1992. In 1992, the proposal was made by the Secretariat and after considering this proposal the General Conference requested the Director General to prepare a report on a possible programme of activities on education and training in radiological protection and nuclear safety in its resolution RES1584. In response to this request and as a first step, the Secretariat prepared a Standard Syllabus for the Post- graduate Educational Course in Radiation Protection. Subsequently, planning of specialised training courses and workshops in different areas of Standard Syllabus were also made. A similar approach was taken to develop basic professional training in nuclear safety. In January 1997, Programme Performance Assessment System (PPAS) recommended the preparation of a standard syllabus for nuclear safety based on Agency Safely Standard Series Documents and any other internationally accepted practices. A draft Standard Syllabus for Basic Professional Training Course in Nuclear Safety (BPTC) was prepared by a group of consultants in November 1997 and the syllabus was finalised in July 1998 in the second consultants meeting. The Basic Professional Training Course on Nuclear Safety was offered for the first time at the end of 1999, in English, in Saclay, France, in cooperation with Institut National des Sciences et Techniques Nucleaires/Commissariat a l'Energie Atomique (INSTN/CEA). -
16. Fission and Fusion Particle and Nuclear Physics
16. Fission and Fusion Particle and Nuclear Physics Dr. Tina Potter Dr. Tina Potter 16. Fission and Fusion 1 In this section... Fission Reactors Fusion Nucleosynthesis Solar neutrinos Dr. Tina Potter 16. Fission and Fusion 2 Fission and Fusion Most stable form of matter at A~60 Fission occurs because the total Fusion occurs because the two Fission low A nuclei have too large a Coulomb repulsion energy of p's in a surface area for their volume. nucleus is reduced if the nucleus The surface area decreases Fusion splits into two smaller nuclei. when they amalgamate. The nuclear surface The Coulomb energy increases, energy increases but its influence in the process, is smaller. but its effect is smaller. Expect a large amount of energy released in the fission of a heavy nucleus into two medium-sized nuclei or in the fusion of two light nuclei into a single medium nucleus. a Z 2 (N − Z)2 SEMF B(A; Z) = a A − a A2=3 − c − a + δ(A) V S A1=3 A A Dr. Tina Potter 16. Fission and Fusion 3 Spontaneous Fission Expect spontaneous fission to occur if energy released E0 = B(A1; Z1) + B(A2; Z2) − B(A; Z) > 0 Assume nucleus divides as A , Z A1 Z1 A2 Z2 1 1 where = = y and = = 1 − y A, Z A Z A Z A2, Z2 2 2=3 2=3 2=3 Z 5=3 5=3 from SEMF E0 = aSA (1 − y − (1 − y) ) + aC (1 − y − (1 − y) ) A1=3 @E0 maximum energy released when @y = 0 @E 2 2 Z 2 5 5 0 = a A2=3(− y −1=3 + (1 − y)−1=3) + a (− y 2=3 + (1 − y)2=3) = 0 @y S 3 3 C A1=3 3 3 solution y = 1=2 ) Symmetric fission Z 2 2=3 max.