**1. NAME AND TITLE**

TREEDE: Monte Carlo Neutron Transport Code System Based on the Track Rotation Estimator.

**2. CONTRIBUTOR**

Physics Department, Ben Gurion University of the Negev, Beersheva, Israel.

**3. CODING LANGUAGE AND COMPUTER**

Fortran IV; CDC.

**4. NATURE OF PROBLEM SOLVED**

TREEDE calculates flux at a point due to a point source. Each particle's track crossing a sphere whose radius equals the source to detector distance is rotated such that the rotated track passes through the detector point and a score is made for the flux at the point. Compensating weights are applied depending on the relation between the original and rotated random walks.

**5. METHOD OF SOLUTION**

The Monte Carlo method based on the concept of the track rotation estimator is used.

**6. RESTRICTIONS OR LIMITATIONS**

None noted.

**7. TYPICAL RUNNING TIME**

The time required for processing 2 × 10^{5} source particles on the CDC 7600 for a finite slab of
dimensions:

is 140 seconds.

**8. COMPUTER HARDWARE REQUIREMENTS**

A CDC computer is required.

**9. COMPUTER SOFTWARE REQUIREMENTS**

A Fortran IV compiler is required.

**10. REFERENCES**

"TREEDE Users' Guide" (Informal Report).

A. Dubi, Y. S. Horowitz, and H. Rief, "Calculation of the Total Flux at a Point by the Monte Carlo Track Rotation Estimator," Informal Paper.

"Flow Chart for the Tracking of a Particle in the Program 'TREEDE'".

**11. CONTENTS OF CODE PACKAGE**

Included are the referenced document and one (1.2MB) DOS diskette which contains the source code.

**12. DATE OF ABSTRACT**

November 1978; revised February 1983.

**KEYWORDS:** MONTE CARLO; SLAB; NEUTRON