1. NAME AND TITLE

ASTROS: Calculation of Primary and Secondary Proton Dose Rates in Spheres and Slabs of Tissue.

AUXILIARY ROUTINES

TAPE GEN: Input Data Generator.

This code package is retained by RSIC to preserve space technology developed in the 1960s.

2. CONTRIBUTOR

Lawrence Radiation Laboratory, Berkeley, California.

3. CODING LANGUAGE AND COMPUTER

FORTRAN IV and MAP; IBM 7090 and 7094.

4. NATURE OF PROBLEM SOLVED

ASTROS was developed for the depth-dose relation in spheres of tissue due to primary protons and to cascade, evaporation, and hydrogen elastically scattered secondary protons.

The code was designed to calculate depth-dose profiles from isotropic fluxes of monoenergetic protons in mammals from mouse size to man size.

5. METHOD OF SOLUTION

The treatment of primary protons is simplified by neglecting straggling and approximating the range-energy relation by R = pEq, where p and q are constants over each of five energy intervals and E and R are respectively the energy and corresponding range of the protons.

Three classes of secondary protons are considered: cascade, evaporation and recoil protons, and for all three classes a Monte Carlo code based on a nuclear model of Metropolis has been used to estimate the energy spectrum and number of secondary protons created.

6. RESTRICTIONS OR LIMITATIONS

The code may be used to calculate doses in spheres from 2 to 25 cm. in radius.

7. TYPICAL RUNNING TIME

No study has been made by RSIC as to typical running time. Estimated running time of sample problem: TAPE GEN, 0.16 hours, and ASTROS, 0.05 hour.

8. COMPUTER HARDWARE REQUIREMENTS

The code was originally designed for the IBM 7044 computer. It is now operable on the IBM 7090 and 7094 with 6 tape units.

9. COMPUTER SOFTWARE REQUIREMENTS

The code may be compiled and executed on the FORTRAN IV IBJOB Monitor in the IBSYS Operating System on the IBM 7090 and 7094. Standard I-O and systems tapes and three scratch tapes are assigned.

10. REFERENCES

R. Wallace, P. G. Steward, and C. Sondhaus, "Primary and Secondary Proton Dose Rates in Spheres and Slabs of Tissue," UCRL-10980 Rev. (July 1964).

P. G. Steward, "Results of Computations of Depth Dose in Tissue Irradiated by Protons," UCRL-16154 (May 1965).

11. CONTENTS OF CODE PACKAGE

Included are the referenced documents and one (1.2MB) DOS diskette which contains the source codes and input and output data for a sample problem for each code in the package.

12. DATE OF ABSTRACT

January 1968; updated July 1981, February 1985.