RSIC CODE PACKAGE CCC-165

1. NAME AND TITLE

DOSE1: Gamma-Radiation Dosimetry for Arbitrary Source and Target Geometry.

This code system was originally developed(1) in the pre-1968 formalism of radiobiologic dosimetry(2) in the Biological and Medical Research Division of Argonne National Laboratory. It was specialized for several specific problems and some computational results were published.(3),(4) The present version, in the currently accepted formalism(5) of absorbed fractions, is intended for general application or as a base for specialized codes. The name given above signifies that the result (which is the first collision absorbed fraction) can be used to calculate the first collision dose.

2. CONTRIBUTOR

Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee.

3. CODING LANGUAGE AND COMPUTER

FORTRAN IV; IBM 360.

4. NATURE OF PROBLEM SOLVED

DOSE1 calculates the first collision absorbed fraction (i.e., the average fraction of the energy lost by all emitted photons on their first collision) and point specific absorbed fractions for a monoenergetic, gamma-ray source. Arbitrary placements of source(s), attenuating material and absorbing material is possible.

To the extent that the first collision absorbed fraction is desired, the only approximation in the calculation arises from the division of the space into small Cartesian units.

5. METHOD OF SOLUTION

The space is subdivided into rectangular parallelepipeds each of which is considered uniform in attenuation, while the absorption and the activity are considered to reside at the center of the parallelepiped. The attenuation is calculated for each ray according to the length of the ray within each parallelepiped. The contribution from all source points is integrated for each parallelepiped.

6. RESTRICTIONS OR LIMITATIONS

The space is divided into 15 subunits in each of the three dimensions. This limits the detail available for spacial accuracy. This can easily be changed; however, the general problem can easily become excessive in computer time. Specialized problems in which some conditions (such as a point source, or uniform attenuation) can be applied, can be programmed to run much faster.

7. TYPICAL RUNNING TIME

For arbitrary source and target volumes execution time will vary approximately as N7/3 where N is the number of elementary subvolumes. For small values of N (i.e., N < 50) execution times are a few seconds on the IBM 360/91.

8. COMPUTER HARDWARE REQUIREMENTS

DOSE1 is operable on the IBM 360/75/91 systems. It should run without major modifications on most computers using FORTRAN IV or similar FORTRAN. It requires about 16,000 (32 bit) words on the 360/75/91.

9. COMPUTER SOFTWARE REQUIREMENTS

The code is written in FORTRAN and the statements have been chosen for compatibility with other computer hardware. The standard monitor and only common FORTRAN supplied subprograms are used (e.g., ALOG, SQRT).

10. REFERENCES

a. Included in package:

L. B. Hubbard, "A FORTRAN Program for Gamma-Radiation Dosimetry for Arbitrary Source and Target Geometry," ORNL-TM-3398 (April 1971).

b. Background information:

11. CONTENTS OF CODE PACKAGE

Included are the referenced document (10.a) and one (1.2MB) DOS diskette which contains the source code and sample problem input. Output from the sample problem is listed in documentation.

12. DATE OF ABSTRACT

June 1972; revised December 1984.

KEYWORDS: KERNEL; GAMMA-RAY; COMPLEX GEOMETRY

1. 1. L. B. Hubbard and F. S. Williamson, "Argonne National Laboratory Biological and Medical Research Division Annual Report," ANL-7409, 1969, p. 250.

2. 2. ICRU report 10a and 10e, Handbook 88 (National Bureau of Standards, Washington, D. C.), 1962.

3. 3. L. B. Hubbard and F. S. Williamson, Physics in Medicine and Biology, 14, 255 (1969).

4. 4. L. B. Hubbard, Radiation Research 44, 4 (1970).

5. 5. R. Loevinger and M. Berman, Physics in Medicine and Biology, 13, 205 (1968).