## RSICC CODE PACKAGE PSR-305

### 1. NAME AND TITLE

EXIFON2.0: A
Model for Statistical Multistep Direct and Multistep Compound Reactions.

**AUXILIARY CODES: **

INPEXI creates input files (if they do not already exist)
from mass tables.

MAKE6 transforms EXIFON output into a (restricted) ENDF-6
format.

### 2. CONTRIBUTOR

Technische Universität Dresden, Germany, through NEA Data Bank,
France.

### 3. CODING LANGUAGE AND COMPUTER/OPERATING SYSTEM

Fortran 77; IBM PC/XT, IBM PC/AT (P00305IPCXT01).

### 4. NATURE OF PROBLEM SOLVED

The EXIFON code is based on an analytical model for statistical
multistep direct and multistep compound reactions (SMD/SMC model). It predicts emission
spectra, angular distributions, and activation cross sections for neutrons, protons,
alpha particles, and photons. Multiple particle emissions are considered for up
to three decays of the compound system. EXIFON is a fast, easy-to-handle code which
predicts cross sections from one global parameter set. The only adjustable quantity
is the pairing shift. The INPEXI code creates input files for EXIFON2.0 from mass
and shell-correction tables. The MAKE6 code transforms EXIFON output into an ENDF-6
format file.

### 5. METHOD OF SOLUTION

The model is based on random matrix physics with the use of the
Green’s function formalism. All calculations are performed without any free parameters.
Results are presented for bombarding energies below 30 MeV.

### 6. RESTRICTIONS OR LIMITATIONS

None noted.

### 7. TYPICAL RUNNING TIME

The sample problem (as listed in RUN.BAT, using the FE56 data)
took about 50 seconds on an IBM PC/AT with a math co-processor.

### 8. COMPUTER HARDWARE REQUIREMENTS

IBM PC and compatibles with math co-processor.

### 9. COMPUTER SOFTWARE REQUIREMENTS

The code was written in Fortran 77 and uses RM Fortran Version
2.42 or Microsoft Fortran Version 4.01.

### 10. REFERENCES

H. Kalka, “EXIFON – A Statistical Multistep Reaction
Code,” Technische Universität Dresden EXIFON (May 1991).

H. Kalka, “Statistical Multistep Reaction Model for Nuclear Data,”
(September 1991).

### 11. CONTENTS OF CODE PACKAGE

The package includes the referenced documents, executables, Fortran
source code, sample input and output files in a self-extracting file.

### 12. DATE OF ABSTRACT

March 1991, August 2001, July 2012.

**KEYWORDS**: MICROCOMPUTER; NEUTRON; NUCLEAR MODELS;
PROTON