1. NAME AND TITLE

ENBAL2: A Program to Generate Multigroup Neutron Kerma Factors.

ENBAL2 is a development from an earlier program, ENBAL, which employs a greater flexibility of use of available cross sections, improved efficiency in data handling, and revised treatment of inelastic scattering to the continuum.

2. CONTRIBUTOR

University of Birmingham, Birmingham, England.

3. CODING LANGUAGE AND COMPUTER

Fortran IV; IBM 370, 3033.

4. NATURE OF PROBLEM SOLVED

ENBAL2 generates multigroup neutron and gamma-ray kerma factors from multigroup cross sections. It has a number of options for the format of output of the kerma factors, including formats enabling direct use of the values in transport codes such as ANISN.

5. METHOD OF SOLUTION

In order to obtain an expression for the kerma factor, ENBAL2 considers the rate of energy deposition in four types of neutron interaction: elastic scattering, inelastic scattering, charged particle producing reactions such as (n,p) and radiative capture. Multigroup kerma factors are computed directly from multigroup neutron cross sections, provided sufficient partial cross section data is available, together with reaction Q-values and inelastic level energies.

Energy deposition by neutrons in each energy group is obtained by considering the total energy balance for each reaction type. For inelastic scattering to the continuum, unless a partial group-to-group transfer matrix is available, excitation of the residual nucleus is modeled by an evaporation spectrum.

6. RESTRICTIONS OR LIMITATIONS

None noted.

7. TYPICAL RUNNING TIME

No study has been made by RSIC of typical running times for ENBAL2.

8. COMPUTER HARDWARE REQUIREMENTS

ENBAL2 is operable on the IBM 370 or IBM 3033 computers.

9. COMPUTER SOFTWARE REQUIREMENTS

A Fortran IV compiler is required.

10. REFERENCE

N. P. Taylor, "ENBAL2, A Programme to Generate Multigroup Neutron Kerma Factors."

11. CONTENTS OF CODE PACKAGE

Included are the referenced document and one (1.2MB) DOS diskette which contains the source code and sample problem input and output.

12. DATE OF ABSTRACT

April 1984.