**RSICC CODE PACKAGE CCC-672**

**1. NAME AND TITLE**

KERNEL: Monte Carlo Code System for Electron (Positron) Dose Kernel Calculation.

**2. CONTRIBUTOR**

Radiation Detection Laboratory, Unite de Development des Technologies du Silicium, Algiers, Algeria.

**3. CODING LANGUAGE AND COMPUTER**

Fortran 77; IBM PC (C00672IBMPC00).

**4. NATURE OF PROBLEM SOLVED**

KERNEL performs dose kernel calculations for an electron (positron) isotropic point source in an infinite homogeneous medium. First, the auxiliary code PRELIM is used to prepare cross section data for the considered medium. Then the KERNEL code simulates the transport of electrons and bremsstrahlung photons through the medium until all particles reach their cutoff energies. The deposited energy is scored in concentric spherical shells at a radial distance ranging from zero to twice the source particle range.

**5. METHOD OF SOLUTION**

KERNEL is based on the general purpose Monte Carlo GEPTS (Gamma, Electron and Positron Transport System) code system. For gamma-rays, KERNEL takes account of photoelectric effect, incoherent and coherent scattering, and pair production. Electrons and positrons are transported according to a continuous slowing down model using collision and radiative stopping powers, multiple scattering distributions and energy straggling functions (optional). Bremsstrahlung gamma-rays and secondary electrons are generated above user-specified thresholds. Homogeneous media with arbitrary compositions can be considered.

**6. RESTRICTIONS OR LIMITATIONS**

The electron and positron dynamic energy range is from 10 keV to 100 MeV while the photon energy range goes from 1keV to 100MeV. Because electron and positron transport is not performed under 10 KeV, it is recommended to use KERNEL with source energy greater than 30 keV.

**7. TYPICAL RUNNING TIME**

Using a Pentium, it takes about 16 minutes to calculate the dose kernel distribution due to 50000 initial electrons with energy of 1 MeV in an infinite water medium.

**8. COMPUTER HARDWARE REQUIREMENTS**

The system runs on IBM PC and compatible computers.

**9. COMPUTER SOFTWARE REQUIREMENTS**

The Microsoft Fortran 5.1 compiler was used to create the included executable which runs under DOS or in a DOS window of Windows 95.

**10. REFERENCE**

O. Chibani, "A Monte Carlo Code for the Electron (Positron) Dose Kernel Calculation," Informal report (1999).

**11. CONTENTS OF CODE PACKAGE**

Included are the referenced document and one diskette on which the source, PC executable, data and test case are distributed in a self-extracting compressed DOS file.

**12. DATE OF ABSTRACT**

May 1999.

** KEYWORDS:** COMPLEX GEOMETRY; ELECTRON; GAMMA-RAY; KERNEL;
MONTE CARLO; POSITRON