NUCLEAR DATA AND MEASUREMENTS REPORTS
ANL/NDM-161 | Complete PDF file (1.8MB)
Neutron Scattering from the Standard 197Au
Alan B. Smith
Differential neutron "elastic scattering" cross sections of elemental gold are measured from ≈ 4.5 - 10.0 MeV at incident-neutron energy intervals of ≈ 0.5 MeV. These results are combined with those of previous and lower-energy work by the author and associates to form a neutron-scattering database extending from ≈ 0.3 - 10.0 MeV. This database is augmented with several additional scattering distributions and with detailed neutron total cross sections from the literature. The resulting composite database is interpreted in terms of optical-statistical, dispersion and coupled-channels models. The results are compared with relevant models in the literature, and a collective rotational model for the prediction of neutron interactions in this mass-energy region is proposed. The experimental and model results are compared with relevant portions of the ENDF/B-VI gold evaluated nuclear data file. Future work is suggested.
Measured neutron dσ/Ωel for 197Au,4.5 → 10.0 MeV. Optical-statistical, coupled-channels, dispersion and "regional" models. Comparisons with ENDF/B-VI
ANL/NDM-162 | Complete PDF file (1.9MB)
Evaluated Decay Data for 206Tl
Filip G. Kondev
Evaluated decay data for the 206Tl nuclide are presented, including recommended values for the half-life, β− and γ−ray emission energies and probabilities. Data on X-ray radiations, Auger and conversion electron energies and emission probabilities are also tabulated.
ANL/NDM-163 | Complete PDF file (2.6MB)
Remark on:- The Neutron Spherical Optical-Model Absorption
Alan B. Smith
The energy-dependent behavior of the absorption term of the spherical neutron optical potential for doubly magic 208Pb and the neighboring 209Bi is examined. These considerations suggest a phenomenological model with an intuitively attractive energy dependence of the imaginary potential that provides a good description of the observed neutron cross sections and that is qualitatively consistent with theoretical concepts. At the same time it provides an alternative to some of the arbitrary assumptions involved in many conventional optical model interpretations reported in the literature and reduces the number of the parameters of the model.
The properties of the optical-statistical and coupled-channels models in the region of the doubly closed shell at A = 208 are examined with particular attention to the energy dependence of the imaginary potential. A new imaginary potential shape is proposed.
ANL/NDM-164 | Complete PDF file (969KB)
Evaluated Decay Data for 246Cm
Filip G. Kondev
Evaluated decay data for the 246Cm nuclide are presented, including recommended values for the half-life, α− and γ−ray emission energies and probabilities. Data on X-ray radiations, Auger and conversion electron energies and emission probabilities are also tabulated.
ANL/NDM-165 | Complete PDF
Fast Neutron, Calcium, Models and Potentials
Alan B. Smith
The experimental neutron cross sections of elemental Calcium were assembled from the world data centers up to incident-neutron energies of ≈ 50 MeV. These results were interpreted in terms of spherical optical and vibrational coupled-channels models, assuming elemental Calcium is essentially the isotope Ca-40, doubly magic with equal numbers of neutrons and protons (20) and thus has zero iso-spin. The model results are compared with various evaluated files and with the predictions of the calculational systems widely used in evaluations.
Fast neutrons incident on doubly-magic, iso-spin zero, Ca-40 are considered. Comparisons of experimental and evaluated quantities and, spherical and vibrational model predictions are discussed. An energy dependent asymmetric shape of the surface-imaginary absorption is proposed.
ANL/NDM-166 | Complete PDF file (481KB)
A Unified Monte Carlo Approach to Fast Neutron Cross Section Data Evaluation
Donald L. Smith
A unified Monte Carlo (UMC) approach to fast neutron cross section data evaluation that incorporates both model-calculated and experimental information is described. The method is based on applications of Bayes Theorem and the Principle of Maximum Entropy as well as on fundamental definitions from probability theory. This report describes the formalism, discusses various practical considerations, and examines a few numerical examples in some detail.
NUCLEAR DATA EVALUATION. Monte-Carlo. Probability. Bayes Theorem. Experimental uncertainties. Nuclear modeling uncertainties. Covariances.
ANL/NDM-167 | Complete PDF file (1.2MB)
Total Absorption Gamma-ray Spectrometer (TAGS) Simulations with GEANT4
Michael L. Smith
This project aims to study the structure of neutron-rich fission products of importance to Advanced Fuel Cycle applications. The measurement of ß-decay feeding intensities is made possible through the use of the Total Absorption Gamma-ray Spectrometer (TAGS) method, utilising a large NaI scintillator detector. The method relies heavily on the modelling of the detector response using a Monte Carlo model. This report looks at the progress of developing such a model (using Geant4) and the other considerations required to implement the TAGS method.
NUCLEAR DATA EVALUATION. Advanced Fuel Cycle. β-decay feeding intensities. Total Absorption Gamma-ray Spectrometer. Monte Carlo.
ANL/NDM-168 | Complete PDF
Report on the Workshop "Decay Spectroscopy at CARIBU: Advanced Fuel Cycle Applications, Nuclear Structure and Astrophysics", April 14-16, 2011, Argonne National Laboratory, USA
M.P. Carpenter1, P. Chowdhury2, J.A. Clark1, F.G. Kondev3, C.J. Lister1, A.L. Nichols4 and D. Seweryniak1
1 Physics Division, Argonne National Laboratory, 2 University of Massachusetts Lowell, 3 Nuclear Engineering Division, Argonne National Laboratory, 4 University of Surrey
The primary aims of the CARIBU workshop were to stimulate interest
in, and discuss the opportunities for, nuclear physics studies at the CAlifornium Rare Isotope Breeder
Upgrade (CARIBU) ion source at the ATLAS facility. Particular emphasis was placed on advance fuel cycle
(AFC), nuclear structure and astrophysics research studied through decay studies of fission fragments.
The workshop was attended by over 70 nuclear physicists from around the world (of which approximately
20 came from Argonne National Laboratory).
CARIBU. Advanced Fuel Cycle. Nuclear Structure. Astrophisics. Nuclear Physics Studies. Decay Studies of Fission Fragments.
Last Modified: Thu, March 8, 2012 6:06 PM