RSIC COMPUTER CODE PSR-004
1. NAME AND TITLE
HEITLER: Cross Section Generator.
UKAEA Atomic Energy Research Establishment, Harwell, England, through the NEA Computer
Programme Library, Ispra (Varese), Italy.
3. CODING LANGUAGE AND COMPUTER
Fortran; IBM 7090 and 7030.
4. NATURE OF PROBLEM SOLVED
HEITLER computes the Compton, photoelectric, pair-production, and total microscopic cross
sections for any element in the range of atomic numbers from 1 to 94 inclusive, for any photon energy
in the range of 10 keV to 20 MeV inclusive. It also computes either the Compton absorption cross
section or the Klein-Nishina differential scattering cross section as desired.
5. METHOD OF SOLUTION
The Compton cross sections are computed analytically. The photoelectric and pair-production
cross sections are obtained by suitable interpolation in atomic number and energy using a compilation
of 25 sets of measured cross sections.
6. RESTRICTIONS OR LIMITATIONS
7. TYPICAL RUNNING TIME
No study has been made by RSIC of typical running times for HEITLER.
8. COMPUTER HARDWARE REQUIREMENTS
HEITLER was designed for the IBM 7030 computer and is also operable on the IBM 7090
9. COMPUTER SOFTWARE REQUIREMENTS
HEITLER was written in basic Fortran in order to minimize conversion problems. It has been
compiled on the IBM 7030 S2 System and on the IBM 7090 IBSYS Operating System.
A. Foderaro, "Subroutine HEITLER," AERE-M 1956 (September 1967).
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.
12. DATE OF ABSTRACT
KEYWORD: GAMMA-RAY CROSS SECTION PROCESSING