RSICC CODE PACKAGE PSR‑146

1. NAME AND TITLE

ALICE-91: Statistical Model Code System with Fission Competition.

2. CONTRIBUTORS

Lawrence Livermore National Laboratory, Livermore, California.

International Atomic Energy Agency, Vienna, Austria, through the Nuclear Energy Agency Data Bank, Issy-les-Moulineaux, France.

3. CODING LANGUAGE AND COMPUTER

Fortran 77; IBM PC, Cray, and SUN (P00146MNYCP02).

4. NATURE OF PROBLEM SOLVED

Several types of calculations and combinations can be performed including a standard Weisskopf-Ewing evaporation with multiple particle emission, s-wave approximation to give an upper limit to the enhancement of gamma-ray deexcitation due to angular momentum effects, and an evaporation calculation that can include fission competition via the Bohr-Wheeler approach. ALICE91 calculates precompound decay via Hybrid and GDH models with multiple precompound decay algorithms, single and double differential spectra, and reaction product cross sections.

The last significant changes to the ALICE source code were made in 1991. Since that time, the only changes made were to allow compilation and execution on updated computer systems. Marshall Blann has retired, and it is unlikely that ALICE will be upgraded. Users are advised to consider other codes such as PRECO-2006 or GNASH-FKK that are still maintained.

In the June 2007 update, a new executable created under WindowsXP SP2 with the Lahey Fortran 95 v7.1 compiler was added to the package. No source code changes were required. This update was necessary because Lahey F77L3-EM/32 Version 5.2 executables in the previous release are incompatible with WindowsXP and generate stack fault errors when invoked. Also in this update, the Windows PC package and the existing CRAY (P00146CYXMP00) and SUN (P00146SUN0401) versions were merged to create the P00146MNYCP02 package.

5. METHOD OF SOLUTION

ALICE/85/300 and later revisions of the ALICE/LIVERMORE 82 computer code do precompound, compound/statistical fission calculations in the general framework of the Weisskopf-Ewing evaporation model, the Bohr-Wheeler transition state model for fission, and the hybrid/geometry dependent models for precompound decay. ALICE/85/300 allows a variable energy mesh size, excitation energies up to 300 MeV, and incorporates several other improvements in calculational approaches.

ALICE91 includes options for shell dependent level densities, and an option to use systematics for angular distribution and also includes gamma-ray competition with particle decay modes.

The Sun version was converted from the Cray ALICE-91 that was released in April, 1991. This version differs from earlier releases in the following ways: 1) Level density options due to Katoria/Ramamurthg may be selected.; 2) Level density options due to ignatyuk may be selected.; 3) The systematics expressions for precompound angular distributions of C. Kalboch are an option. (These are faster than the option based on n-n scattering kinematics and agree more with experimental results.); 4) Gamma-ray spectra are given for the reactions, and gamma rays compete with nucleon emission (Mitigates problems with trapped protons for very proton rich nuclei.; 5) This version may be used to calculate for isotopically mixed targets (e.g. natural isotopic composition).

6. RESTRICTIONS OR LIMITATIONS

Users must refer to comments in the Fortran source files for input instructions and information.

7. TYPICAL RUNNING TIME

The sample input took about 6 seconds of CPU time on the Cray XMP under UNICOS.

8. COMPUTER HARDWARE REQUIREMENTS

Versions are available for 3 computers: Cray XMP, IBM486, Sun workstations, or PC486 or better computers.

9. COMPUTER SOFTWARE REQUIREMENTS

The executable, which is included with the ALICE-91 PC version, was created under WindowsXP SP2 with the Lahey Fortran 95 v7.1 compiler. This executable also runs under Windows Vista. The Cray and Sun versions were not modified in the 2007 update, and are being retained for archival purposes. The Cray/CTSS version used the CIVIC compiler and the Cray/UNICOS version used the CFT77 compiler. The Sun version was tested with the SC1.0 f77 compiler, a Sun SPARCstation SLC under SunOS 4.1.1 using SUN FORTRAN v1.4, and on a Sun SPARCstation 2.0 under SOLARIS 2.3 (Sun 5.3) using SUN FORTRAN 2.0.

10. REFERENCES

a. Included in the documentation:

M. Blann, “CODE ALICE/85/300,” UCID‑20169 (September 1984).

M. Blann and J. Bisplinghoff, “CODE ALICE/LIVERMORE 82,” UCID‑19614 (November 1982).

R. Roussin, Informal Input Instructions for ALICE/85/300 (February 1987).

M. Blann and H. K. Vonach, “Global Test of Modified Precompound Decay Models,” Physical Review C, 28(4), 1475‑1492 (October 1983).

D. E. Cullen and V. Goulo, “Precompound Nuclear Model Code Version for Personal Computer IBM/AT,” IAEA-NDS-93, Rev. 0 (May 1988).

M. Blann, “Recent Progress and Current Status of Preequilibrium Reaction Theories and Computer Code ALICE,” UCRL-JC-109052 (Preprint)(November 21, 1991).

b. Background information:

M. Blann, “Recent Progress and Current Status of Pre-equilibrium Reaction Theories and Computer Code ALICE,” in SMR/284‑1, ICTP Workshop on Applied Nuclear Theory and Nuclear Model Calculations for Nuclear Technology Applications held in Trieste, Italy (February-March, 1988, and February-March, 1992).

M. Blann, “Multiple Pre-equilibrium Decay Processes,” UCRL‑97778, from the NEANDC Specialists' Meeting on Pre-equilibrium Nuclear Reactions held in Semmerling, Austria (February 1988).

Jens Bisplinghoff, “Configuration Mixing in Pre-equilibrium Reactions: A New Look at the Hybrid-Exciton Controversy,” Physical Review C, 33(5), 1569‑1580 (May 1986).

M. Blann and J. Bisplinghoff, “Numerical Test of Approximations in the Hybrid Precompound Decay Model,” Atomic Nuclei, 326, 429‑434 (1987).

M. Blann and T. T. Komoto, “Precompound Evaporation Analyses of Excitation Functions for (alpha,xn) Reactions,” Physical Review C, 29(5), 1678‑1683 (May 1984).

G. Reffo, M. Blann, B. A. Remington, “On the Origin of Medium Energy Gamma-Rays in Nuclear Reactions,” UCRL‑97866, Preprint submitted to Physical Review C (December 1987).

M. Blann, W. Scobel, and E. Plechaty, “Precompound Nucleon Angular Distributions in the Continuum,” Physical Review C, 30(5), 1493‑1508 (November 1984).

M. Blann, G. Reffo, F. Fabbri, “Calculation of Gamma-Ray Cascades in Code ALICE,” UCRL‑55374, Preprint submitted to Nuclear Instruments and Methods (September 1986).

F. Plasil, “ORNL ALICE: A Statistical Model Computer Code Including Fission Competition,” ORNL/TM‑6054, (November 1977).