NUCLEAR DATA AND MEASUREMENTS REPORTS
ANL/NDM-143 | Abstract only (18 KB PDF file) | Complete PDF file (1.8 MB)
A Compilation of Information on the 32S(p,g )33Cl Reaction and Properties of Excited Levels in 33Cl
Roy E. Miller and Donald L. Smith
ANL/NDM-144 | Abstract only (34 KB PDF file) | Complete PDF file (8.91 MB)
A Compilation of Information on the 31P(p,a )28Si Reaction and Properties of Excited Levels in the Compound Nucleus 32S
Roy E. Miller and Donald L. Smith
The following additional files associated with this report can be downloaded The text files (*.txt) can be viewed with a text editor.
- ABAREX Fortran Source – 98rev (Text) ABAREX-Fortran98rev.txt (515 KB text file)
- ABAREX Example 3.1 (Text) ABAREX-Example31.txt (2 KB text file)
- ABAREX Example 3.2 (Text) ABAREX-Example32.txt (3 KB text file)
- ABAREX Example 3.3 (Text) ABAREX-Example33.txt (5 KB text file)
- ABAREX Example 3.4 (Text) ABAREX-Example34.txt (3 KB text file)
- ABAREX Example 4.1 (Text) ABAREX-Example41.txt (5 KB text file)
- ABAREX Example 4.2 (Text) ABAREX-Example42.txt (5 KB text file)
- ABAREX Example 5.1 (Text) ABAREX-Example51.txt (5 KB text file)
- ABAREX Example 5.2 (Text) ABAREX-Example52.txt (5 KB text file)
- ABAREX Example 6.1 (Text) ABAREX-Example61.txt (14 KB text file)
- ABAREX Example 6.2 (Text) ABAREX-Example62.txt (23 KB text file)
- ABAREX Example 6.2a (Text) ABAREX-Example62a.txt (37 KB text file)
- ABAREX Example 6.2b (Text) ABAREX-Example62b.txt (20 KB text file)
- ABAREX Example 6.2c (Text) ABAREX-Example62c.txt (23 KB text file)
- ABAREX Example 6.2d (Text) ABAREX-Example62d.txt (20 KB text file)
ANL/NDM-146 | Abstract only (30 KB PDF file) | Complete PDF file (6.7 MB)
Non-Destructive Assay of EBR-II Blanket Elements Using Resonance Transmission Analysis
Raymond T. Klann and Wolfgang P. Poenitz
- ABAREX-EL Fortran Source (Text) ABAREX-EL-Fortran.txt (567 KB text file)
- ABAREX-EL Example 1 (Text) ABAREX-EL-Example1.txt (13 KB text file)
- ABAREX-EL Example 1a (Text) ABAREX-EL-Example1a.txt (13 KB text file)
- ABAREX-EL Example 1b (Text) ABAREX-EL-Example1b.txt (15 KB text file)
- ABAREX-EL Example 1c (Text) ABAREX-EL-Example1c.txt (14 KB text file)
- ABAREX-EL Example 1d (Text) ABAREX-EL-Example1d.txt (26 KB text file)
- ABAREX-EL Example 1e (Text) ABAREX-EL-Example1e.txt (17 KB text file)
- ABAREX-EL Example 1f (Text) ABAREX-EL-Example1f.txt (25 KB text file)
- ABAREX-EL Example 1g (Text) ABAREX-EL-Example1g.txt (8 KB text file)
- ABAREX-EL Example 1h (Text) ABAREX-EL-Example1h.txt (33 KB text file)
- ABAREX-EL Example 2 (Text) ABAREX-EL-Example2.txt (25 KB text file)
- ABAREX-EL Example 2a (Text) ABAREX-EL-Example2a.txt (21 KB text file)
- ABAREX-EL Example 3 (Text) ABAREX-EL-Example3.txt (52 KB text file)
- ABAREX-EL Example 4 (Text) ABAREX-EL-Example4.txt (40 KB text file)
- ABAREX-EL Example 5 (Text) ABAREX-EL-Example5.txt (53 KB text file)
ANL/NDM-148 | Abstract only (6 KB PDF file) | Complete PDF file (4.21 MB)
A Method to Construct Covariance Files in ENDF/B Format for Criticality Safety Applications
Dimitri G. Naberejnev and Donald L. Smith
Argonne National Laboratory is providing support for a criticality safety analysis project that is being performed at Oak Ridge National Laboratory. The ANL role is to provide the covariance information needed by ORNL for this project. The ENDF/B-V evaluation is being used for this particular criticality analysis. In this evaluation, covariance information for several isotopes or elements of interest to this analysis is either not given or needs to be reconsidered. For some required materials, covariance information does not exist in ENDF/B-V: 233U, 236U, Zr, Mg, Gd, and Hf. For others, existing covariance information may need to be re-examined in light of the newer ENDF/B-VI evaluation and recent experimental data. In this category are the following materials: 235U, 238U, 239Pu, 240Pu, 241Pu, Fe, H, C, N, O, Al, Si, and B. A reasonable estimation of the fractional errors for various evaluated neutron cross sections from ENDF/B-V can be based on the comparisons between the major more recent evaluations including ENDF/B-VI, JENDL3.2, BROND2.2, and JEF2.2, as well as a careful examination of experimental data. A reasonable method to construct correlation matrices is proposed here. Coupling both of these considerations suggests a method to construct covariances files in ENDF/B format that can be used to express uncertainties for specific ENDF/B-V cross sections.
Nuclear data evaluation, data uncertainty, correlation matrix, covariance matrix.
ANL/NDM-148.memo | Complete ANL/NDM-148.memo PDF file (65 KB)
Covariance Files in ENDF/B-V Format for Criticality Safety Applications.
Dmitri G. Naberejnev
DE5COV.zip (1.65 MB ZIP file) - ENDF/B-V tapes with calculated covariace files for isotopes/elements listed in ANL/NDM148.memo
DE5COV_GRA.zip (729 KB ZIP file) - graphical representation of correlation matrices and fractional errors for isotopes/elements listed in ANL/NDM148.memo
ANL/NDM-149 | Abstract only (49.9 KB PDF file) | Complete PDF file (1.04 MB)
Neutrons and Antimony : Physical Measurements and Interpretations
Alan B. Smith
New experimental information for the elastic and inelastic scattering of ≈ 4 - 10 MeV neutrons from elemental antimony is presented. The differential measurements are made at ≈ 40 or more scattering angles and at incident neutron-energy intervals of ≈ 0.5 MeV. The present experimental results, those previously reported from this laboratory and as found in the literature are comprehensively interpreted using spherical optical-statistical and dispersive-optical models. Direct vibrational processes via core-excitation, isospin and shell effects are discussed. Antimony models for applications are proposed and compared with “global” “regional” and “specific” models reported in the literature.
Measured neutron dσ/dΩel and dσ/dΩinel for 4.5-10 MeV neutrons incident on elemental antimony. Comprehensive model interpretations including: - spherical optical-statistical, dispersive and direct-reaction models. Provision of a " general regional" model for applied purposes.
ANL/NDM-150 | Abstract only (49.2 KB PDF file) | Complete PDF file (661 KB)
Neutrons and Antimony : Neutronic Evaluations of 121Sb and 123Sb
Alan B. Smith and Andreas Fessler
The new experimental results and recent extensive model development discussed in the companion report ANL/NDM-149 [Smi00], the new resonance parameterization of ref. [Mug99] and experimental results and models available in the literature, are used to construct neutronic evaluations for 121Sb and 123Sb in the ENDF/B-6 formats. These are comprehensive evaluations extending from thermal energies to 30 MeV, and include all reactions and processes commonly used in applied neutronic calculations. Comparisons are made with ENDF/B-6 MAT 5125 and 5131 files [ENDF].
Comprehensive ENDF/B-6 formatted neutronic evaluations of 121Sb and 123Sb.
ANL/NDM-151 | Abstract only (8 KB PDF file) | Complete PDF file (7.95 MB)
Fast-Neutrons Incident on Holmium
Alan B. Smith
Differential neutron-scattering cross sections of elemental holmium (i.e., 165Ho) are measured at forty or more scattering angles, at ≈ 0.5 MeV incident-energy intervals, from ≈ 4.5 - 10.0 MeV. These new results are combined with neutron total and scattering cross sections previously reported in the literature to obtain as comprehensive an experimental data base as possible. This data is interpreted in the context of spherical-optical, coupled-channels and dispersive models, with particular attention to the collective excitation of the K = 7/2- ground-state rotational band of 165Ho. The effect of the collective properties on the model potentials is discussed. Comparisons are made with previous models reported in the literature and with the relevant portions of the ENDF/B-6 evaluated nuclear data file. Generally, the latter evaluation is supported by the present work. Suggestions for future charged-particle and neutron studies of holmium are made.
Measured neutron dσ/dΩel for Ho, 4.5-10 MeV. Extensive optical and coupled-channels model interpretations.
ANL/NDM-152 | Abstract only (36 KB PDF file) | Complete PDF file (2.8 MB)
Technical Note: - Dispersion Contributions to Neutron Reactions
R.D. Lawson and A.B. Smith
An approach used to calculate the surface- and volume-imaginary potential strengths is presented. It is shown that surface dispersive effects in neutron-induced reactions at lower energies (e.g., < 30 MeV) have a substantive impact on the process. The volume contribution due to dispersive effects is also calculated.
Simple formulation of dispersion effects in neutron reactions.
ANL/NDM-153 | Abstract only (48 KB PDF file) | Complete PDF file (7.59 MB)
Fast-Neutrons Incident on Hafnium
Alan B. Smith
Total neutron cross sections of elemental Hf were measured from ≈ 0.75 - 4.5 MeV, in steps of ≈ 40 keV and with few-keV resolution. Differential elastic scattering cross sections of elemental Hf were measured from ≈ 4.5 - 10.0 MeV , in ≈ 0.5 MeV steps and at 40 scattering angles between ≈17° and 160°. Some additional elastic- and inelastic-scattering results were obtained at incident energies of less than 1.5 MeV. These new data were combined with that found in the literature to obtain as comprehensive an experimental database as possible. It was interpreted in terms spherical-optical-statistical coupled-channels and dispersive-couple-channels models. The physical characteristics of the resulting potentials are discussed. The potentials are a vehicle for extrapolation, evaluation, interpolation and physical calculation for both basic and applied purposes. Comparisons are made with ENDF/ B-6 (MAT 7200).
Measured neutron dσ/dΩ and σt for elemental Hafnium. 0.3-1.5 MeV and 4.5-10 Mev. Optical and coupled-channels model interpretation.
ANL/NDM-154 | Abstract only (50 KB PDF file) | Complete PDF file (0.99 MB)
An Approach for Dealing with Large Errors
Donald L. Smith, Dimitri G. Naberejnev and Laura A. Van Wormer
Numerical functions or equivalent algorithms are commonly used to derive estimates for physical quantities that can be expressed in terms of more fundamental physical parameters. It is shown that in situations where large uncertainties (errors) are involved in these parameters, or where error amplification occurs through severe non-linearity of the functions, conventional deterministic techniques for calculating the derived quantities and estimating their errors can lead to erroneous results. Instead, it is necessary to resort to a probabilistic approach and thereby obtain estimates for mean values and variances of the derived quantities through Monte Carlo simulation in order to preserve the essential information without distortion. The correct choice for a probability distribution is suggested by the inherent nature of the random variable in question. Examples are given from the analysis of radioactivity decay, the shielding of penetrating radiation, and the derivation of nuclear reaction rates that are used in astrophysical calculations to model nucleosynthesis of the elements in stellar explosions. Subsequent analyses that use these derived quantities must also be carried out in a probabilistic manner to insure that the obtained results will reflect the underlying information properly.
DATA ANALYSIS. Errors. Uncertainty. Probability. Non-linearity. Radioactivity. Shielding, Astrophysics.
ANL/NDM-155 | Abstract only (39.2 KB PDF file) | Complete PDF file (2.06 MB)
Fast-Neutron Scattering from Elemental Rhenium
Alan B. Smith
Results of measurements of neutron scattering from elemental rhenium over the incident-energy regions 0.1-1.5 MeV, and 4.5-10.0 MeV are presented. The first of these supplements previously-reported work at this Laboratory, and the second consists of information in a new energy range. These experimental results are interpreted in terms of optical-statistical and coupled-channels models, including consideration of dispersive effects, and of scalar and vector potentials. Some basic and applied physical implications of these considerations are discussed. Comparisons are made with other regional and/or global models, and with evaluated nuclear-data files used in applications.
Measured neutron scattering, 0.3-1.5 MeV and 4.5-10 Mev. Optical-statistical and coupled-channels model analysis of experimental results. Basic and applied physical comments.
ANL/NDM-156 | Abstract only (56.7 KB PDF file) | Complete PDF file (80.3 KB)
A Demonstration of the Lognormal Distribution
Donald L. Smith
Although its applicability is not universal, the lognormal distribution is frequently used to represent physical parameters that are inherently positive and are not well known, i.e., that have large errors. In particular, arguments drawn from Bayesian statistics suggest that the lognormal function is the optimal choice of a probability distribution for those cases where the only knowledge possessed about a particular parameter is an estimate of its mean value and associated error. In this report it is demonstrated by a simulation exercise that the lognormal function represents very well the outcomes of repeated measurements that are subjected to a variety of multiplicative disturbances that, by their very nature, preclude the observation of negative values. In the present study, a simplified model of measurement is defined and it is then subjected to numerical analysis using the Monte Carlo method. There is no attempt to prove rigorously that the lognormal distribution results as the unique consequence of assumptions about the defined model, nor are other more complex models of measurement investigated. In any event, it is not possible to produce a proof by the use of anecdotal information, e.g., by analyzing the results of repeated Monte Carlo trials. Nevertheless, the simulation study described here does provide strong evidence that for many practical situations the lognormal distribution can be used to represent the probable outcome of measurements of positive quantities.
SIMULATION. Monte-Carlo. Probability. Uncertainty. Errors. Lognormal distribution. Experimental perturbations. Experimental modeling.
ANL/NDM-157 | Complete PDF file (1.8
Fast-Neutrons Incident on Gadolinium
Alan B. Smith
Results of measurements of neutron scattering from elemental gadolinium over the incident energy regions of 0.3-1.5 MeV and 4.5-10.0 MeV are presented. These results are interpreted in terms of optical-statistical and coupled-channels models, including consideration of dispersion effects and of scalar and vector potentials. Some basic and applied physical implications of these considerations are noted. Comparisons are made with other regional models, and with ENDF/B-VI evaluated nuclear-data files used in applications.
Measured neutron scattering from Gd at 0.3-1.5 MeV and 4.5-10 MeV. Optical-statistical and coupled-channels model analysis of experimental results. Basic and applied physical comments.
ANL/NDM-158 | Abstract only (17.6 KB PDF file) | Complete PDF file (2.48 MB)
A Survey of Experimental and Evaluated Fast Neutron Helium Production Cross Section Data for Fusion Energy Applications
Donald L. Smith
It is well established that the high fluences of fast neutrons likely to be encountered in the environments of fusion reactors or fusion materials test facilities will generate substantial quantities of helium (both 4He and 3He isotopes), and that the presence of this gas in bulk material can produce serious damage in engineering structures due to swelling. The present study was undertaken to survey the current status (as of early 2004) of the available fast neutron cross section information for helium production in several major structural elements of interest for the development of fusion energy systems. The scope of this study encompasses both compiled experimental cross section data and evaluated cross sections available from major nuclear data libraries used in the analysis of fusion systems. The main conclusion from this work is that the contemporary knowledge of those individual neutron reaction cross sections important for helium production is, in general, very inadequate for the purpose of producing reliable designs for fusion reactors (e.g., ITER) and materials irradiation test facilities (e.g., IFMIF). Since the number of distinct neutron reactions that must be considered is large, and the capabilities (both experimental and theoretical) of the nuclear physics community to adequately determine the cross sections for specific reactions is limited for various reasons, it is recommended, as a consequence of the present investigation, that an engineering approach be undertaken to provide the data needed for system design purposes. The suggested technical approach would involve irradiating small specimens of candidate materials in high fluence neutron fields whose spectra resemble as closely as possible those to be encountered in real fusion facilities, and that direct integrated yield measurements then be made of helium production in these samples, inclusive of all the contributing neutron reaction channels.
SURVEY. Nuclear data, neutron cross sections, helium production, fusion technology.
ANL/NDM-159 | Abstract only (15.5 KB PDF file) | Complete PDF file (1.51 MB)
Covariance Matrices for Nuclear Cross-Sections Derived from Nuclear Model Calculations
Donald L. Smith
The growing need for covariance information to accompany the evaluated cross section data libraries utilized in contemporary nuclear applications is spurring the development of new methods to provide this information. Many of the current general purpose libraries of evaluated nuclear data used in applications are derived either almost entirely from nuclear model calculations or from nuclear model calculations benchmarked by available experimental data. Consequently, a consistent method for generating covariance information under these circumstances is required. This report discusses a new approach to producing covariance matrices for cross sections calculated using nuclear models. The present method involves establishing uncertainty information for the underlying parameters of nuclear models used in the calculations and then propagating these uncertainties through to the derived cross sections and related nuclear quantities by means of a Monte Carlo technique rather than the more conventional matrix error propagation approach used in some alternative methods. The formalism to be used in such analyses is discussed in this report along with various issues and caveats that need to be considered in order to proceed with a practical implementation of the methodology.
SURVEY. Nuclear data, neutron cross sections, helium production, fusion technology. METHODS. Nuclear cross sections, nuclear models, errors, covariances, Monte Carlo.
ANL/NDM-160 | Complete PDF file (2.7 MB)
Fast-Neutrons Incident on Rotors: -Tantalum
Alan B. Smith
Mono-energetic neutrons are scattered from elemental tantalum over two-incident-neutron energy ranges. The first set of data is distributed over E ~ 0.3 - 1.5 MeV, including both elastic and inelastic processes. These results supplement those reported by the author and co-workers some time ago. The second set of data consists of detailed measurements over the energy range E ~ 4.5 -10.0 MeV. The present work is augmented with neutron scattering and totaI-cross-section data 'from the literature to form a composite experimental database. The latter :is interpreted in the context ,of optical-statistical and coupled-channels models, including consideration of collective deformations, dispersive effects, and other physical properties. The results are compared with those of similar neutron interactions in this region of collective deformations. A "regional" model is proposed for the interpretation of such neutron interactions. The model and the experimental results are compared with relevant values given in ENDF/B-VI. Future work is suggested.
Measured neutron scattering 0.3 -10.0 MeV. Optical-statistical and coupled-channels model analysis of experimental results. Basic and applied physical comments. Regional model.
Last Modified: Thu, January 20, 2011 7:15 PM