1. NAME AND TITLE

ICAR: A Code For Combinatorial Calculation of Level Densities

2. CONTRIBUTOR

ENEA, Bologna, Italy, through IAEA, Vienna, through NEA Data Bank, France.

3. CODING LANGUAGE AND COMPUTER

Fortran 77; IBM PC/AT.

4. NATURE OF PROBLEM SOLVED

ICAR performs state and level density calculations for a specified type of nucleon. Calculations can be carried out in terms of the free gas model or in the frame of the BCS formalism to account for the pairing interaction.

5. METHOD OF SOLUTION

The code starts by calculating properties of the ground state, such as the correlation function, chemical potential, total energy and condensation energy. Next all possible configurations of n excitons within the adopted orbitals are generated by means of a combination enumeration algorithm.

6. RESTRICTIONS OR LIMITATIONS

None noted.

7. TYPICAL RUNNING TIME

The sample input problem (test case 5) was run at NEA Data Bank on an IBM PC/AT with a math coprocessor. The problem took about 30 minutes.

8. COMPUTER HARDWARE REQUIREMENTS

ICAR runs on an IBM PC/AT with a math coprocessor.

9. COMPUTER SOFTWARE REQUIREMENTS

The code was written in Fortran 77. The NEA Data Bank used the RM/Fortran compiler, version 2.4 under the MS-DOS 3.20 operating system.

10. REFERENCES

M. Herman, G. Retto, "Chain Of Codes for the Combinatorial Calculation of Level Densities," ISSN/0393-6333; IAEA 0974/01 (July 6, 1988).

M. Herman, "Workshop on Applied Nuclear Theory and Nuclear Model Calculations for Nuclear Technology Applications," SMR/284-9 (February-March 1988).

11. CONTENTS OF CODE PACKAGE

Included are the referenced document and one DS/HD (1.2 MB) 5.25-inch diskette.

12. DATE OF ABSTRACT

November 1990.