Line And Continuum Gamma Ray Yields From Thermal Neutron Capture In 75 Elements

Line and Continuum Gamma-ray Yields from Thermal-neutron Capture in 75 Elements

The document presents the results of an analysis of thermal capture gamma-ray spectral data obtained at the MIT Thermal Capture Gamma-Ray Facility using a Ge(Li)-NaI spectrometer. This data has been previously analyzed to obtain the energies and intensities of the resolved lines from radiative neutron capture in 75 natural elements. In the present work, the spectral data was unfolded to remove the effect of the spectrometer response, and the total gamma-ray yield for both discrete lines and continuum, was determined. The method of analysis, described previously by Harper and Rasmussen, is briefly summarized. Also discussed are the binding energies producing a consistent set of values. A comparison of some of the present results with previous data is given. The capture gamma-ray energies and intensities are tabulated and the original gamma-ray spectra are shown for each element. The total gamma-ray yield data for each element has been written onto magnetic tape in the ENDF format to facilitate the use of this data by radiation transport codes. A description of the tape preparation procedure and the data formats employed are given. (Author).

Database of Prompt Gamma Rays from Slow Neutron Capture for Elemental Analysis

Neutron-capture prompt-gamma activation analysis (PGAA) is particularly valuable as a non-destructive nuclear method in the measurement of elements that do not form neutron capture products with delayed gamma ray emissions. Inaccurate and incomplete data have been a significant hindrance in the qualitative and quantitative analysis of complicated capture gamma spectra by means of PGAA. This database was produced to improve the quality and quantity of required data in order to make possible the reliable application of PGAA in fields such as materials science, geology, mining, archaeology, environment, food analysis and medicine. The database provides a variety of tables for all natural elements (from H to U) including the following data: isotopic composition, thermal radiative cross-section (total and partial), Westcott g-factors, energy of the gamma rays (prompt and delayed), decay mode, half-life and branching ratios. The CD-ROM included in this publication contains the database, the retrieval system and important electronic documents related to the project.

Nuclear Data in Science and Technology