**1. NAME AND TITLE**

KAMCCO: Three-Dimensional Time Dependent Monte Carlo Code System for Fast Neutron Physics Problems.

**2. CONTRIBUTOR**

Gesellschaft fur Kernforschung, Institute for Neutron Physics and Reactor Technology, Karlsruhe, Federal Republic of Germany, through the OECD NEA Data Bank, Gif-sur-Yvette, France.

**3. CODING LANGUAGE AND COMPUTER**

Fortran IV, Assembler language; IBM 370.

**4. NATURE OF PROBLEM SOLVED**

KAMCCO is a three-dimensional Monte Carlo code system designed for fast neutron reactor physics problems. It includes time dependence and a continuous treatment of the energy. The geometry must be defined in terms of surfaces up to second order. Two options are available: (a) census time scheme for time dependent inhomogeneous neutron transport problems, and (b) source iteration for static eigenfunction problems.

Neutron collisions are treated on a per isotope basis. Elastic scattering retains first order anisotropy in the center-of-mass system. Inelastic scattering is processed via the evaporation model or via the excitation of discrete levels, depending on the pre-collision energy.

**5. METHOD OF SOLUTION**

The Monte Carlo techniques are mostly analog. Importance sampling is involved in the collision physics, and Russian roulette and splitting are employed to a minor extent. Estimates are obtained from the collision, the track length estimator, and their linear combination. Eigenfunction problems are handled by a variant of the power method.

**6. RESTRICTIONS OR LIMITATIONS**

The maximum number of isotopes (fissile isotopes) is 30 (10). Most data fields have variable dimensions. The few exceptions can be easily extended by strictly logical changes.

**7. TYPICAL RUNNING TIME**

For a medium sized fast critical assembly (Sneak 3A1) with 8 isotopes, a standard error 0.005 in the static eigenvalue is obtained in 12 minutes on the IBM 370/168.

**8. COMPUTER HARDWARE REQUIREMENTS**

KAMCCO requires at least 230 K bytes of main storage on an IBM 370 computer, but no external storage. The availability of a clock routine which measures CPU time is a great advantage, but not absolutely necessary.

**9. COMPUTER SOFTWARE REQUIREMENTS**

Fortran IV and Assembler compilers and assemblers are required.

**10. REFERENCE**

**a. Included in the documentation:**

G. Arnecke, H. Borgwaldt, V. Brandl, and M. Lalovic, "KAMCCO, A Reactor Physics Monte Carlo Neutron Transport Code," KFK-2190 (June 1975).

**b. Background information:**

G. Arnecke, et al., "KAMCCO, Ein Reaktorphysikalischer Monte-Carlo-Neutronentransport-Code," KFK 2190 (1975) in German.

G. Arnecke, et al., "Efficient Data Management Techniques Implemented in the Karlsruhe Monte Carlo Code KAMCCO," NEA-CRP-L-118 (ANL-75-2), p. 5-17 (1974).

H. Borgwaldt, "Comparison of 3 Methods to Control the Leakage of Particles in a Monte Carlo Game," KFK 1391 (1971).

V. Brandl, "Die Monte-Carlo Berechnung von Quotienten in der Reaktorphysik," KFK 2074 (1975).

B. Hinkelmann, et al., "Status of the Karlsruhe Evaluated Nuclear Data File KEDAK in June 1970," KFK 1340 (1971).

**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**

August 1979; revised March 1982, February 1983, January 1984.

**KEYWORDS:** MONTE CARLO; NEUTRON; TIME-DEPENDENT; COMPLEX GEOMETRY