IAEA1247 CEM95.

1. NAME OR DESIGNATION OF PROGRAM:  CEM95.

3. DESCRIPTION OF PROGRAM OR FUNCTION

The code CEM95 is intended for  the Monte Carlo calculation of nuclear reactions in the framework of the Cascade-Exciton Model (CEM) of nuclear reactions. The CEM assumes that reactions occur in three stages. The first stage is the intranuclear cascade. The excited residual nucleus formed after the  emission of cascade particles determines the particle-hole configuration that is a starting point for the second preequilibrium stage of the reaction. The subsequent relaxation of the nuclear excitation is treated in terms of the exciton model of preequilibrium decay which includes the description of the equilibrium evaporative stage of the reaction.

4. METHOD OF SOLUTION:  Monte Carlo simulation method.

5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM

The CEM95 allows us  to calculate nucleon- and pion- induced reactions for Carbon and heavier targets for incident energies from 10-15 MeV to several GeV.

6. TYPICAL RUNNING TIME

It depends on the concrete characteristics to be calculated: 5 min may be enough to calculate fission cross section at a given energy; tens of ours may be needed to calculate with a good statistics double differential cross sections at backward angles and high energy of ejectiles.

NEA-DB ran the test cases included in this package on both a DEC/VAX 6000 machine and a PC/80486 (66 MHz) microcomputer. The following table summarizes the execution times found:
                           VAX            PC
           Test 1          26min         45min
           Test 2        1h45min       2h40min
           Test 3a          2min          2min
           Test 3b       4h36min       7h40min

7. UNUSUAL FEATURES OF THE PROGRAM

The CEM95 code is intended for calculation of reaction, elastic, fission and total cross sections;  excitation functions; nuclide yields, energy and angular spectra; double differential cross sections; mean multiplicities, i.e., number of ejectiles per incident bombarding particle; ejectile yields; mean energies and production cross sections for neutrons, protons, deuterons, tritons, He3, He4, pions-, pions0, and pions+ emitted in nucleon- and pion-induced reactions using the Cascade-Exciton Model (CEM) of Nuclear Reactions. A detailed description of the CEM may be found in Ref.1. Part of primary version of the code concerning the preequilibrium and equilibrium stages of reactions is published in Ref.2. The Dubna version of the  intranuclear cascade model used in the CEM95 is described in detail  in the monograph 3. A detailed description of the subroutines used at the cascade stage of reaction may be found in Ref.4. All the models incorporated in the CEM95 for description of the level density parameter are given in Ref.5. All the models incorporated in the CEM95 to take into account competition between particle emission and fission at the compound stage of the reactions are described in  Ref.6. Exemplary results obtained with the code CEM95 may be found in Refs.7,8.

8. RELATED AND AUXILIARY PROGRAMS

The code CEM95 is an extension version of the code CEM92M.

10. REFERENCES

- 2) S.G. Mashnik, V.D. Toneev:
  "MODEX - the Program for Calculation of the Energy Spectra of
  Particles Emitted in the Reactions of Pre-Equilibrium and
  Equilibrium Statistical Decays", Communications of the Joint
  Institute for Nuclear Research, P4-8417, Dubna, 1974
  (FORTRAN66, text - in Russian).

- 3) V.S. Barashenkov, V.D. Toneev:
  "Interaction of High Energy Particles and Nuclei with Atomic
  Nuclei", Moscow, "Atomizdat', 1972 (in Russian).

- 4) F.G. Geregi et al.:
  "Calculation of Cross-Sections for Photonuclear Reactions",
  Kishinev, Kishinev State University, 1990 (in Russian).

- 7) S.G. Mashnik:
  Nucl. Phys. A568(1994)703.

- 8) S.G. Mashnik, S.A. Smolyansky:
  "The Cascade-Exciton Approach to Nuclear Reactions (Foundation
  and Achievements)", JINR Preprint E2-94-353, Dubna, 1994.

- S. Mashnick:
  User Manual for the Code CEM95 (1995)
- 1) K.K. Gudima et al.:
  Cascade-Exciton Model of Nuclear Reactions
  Nucl. Phys. A401(1983)329
- 5) S.G. Mashnik:
  Statistical Model Calculations of Nuclear Level Density with
  Different Systematics for the Level Density Parameter
  Acta Phys. Slov. 43(1993), No.2, 86-107
- 6) S.G. Mashnik:
  Optimal Systematics of Single-Humped Fission Barriers
  for Statistical Calculations
  Acta Phys. Slov. 43(1993), No.4, 243-270

11. MACHINE REQUIREMENTS:

The program was installed and run by NEA-DB both on a DEC/VAX 6000-510 computer and a DELL 466/L PC/80486 with 66 MHz and  12 MBytes of RAM.

13. OPERATING SYSTEM UNDER WHICH PROGRAM IS EXECUTED:

The implementation on VAX was done under VMS V.6.1 and  using the VAX FORTRAN compiler version 6.2. The implementation on the PC was done under MS-DOS V.6.20; and the source was compiled with the Microsoft Fortran compiler Version 5.1.

14. OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS:

15. NAME AND ESTABLISHMENT OF AUTHORS

  Dr. Mashnik Stepan
  Laboratory of Theoretical Physics
  Joint Institute for Nuclear Research
  141980 DUBNA
  Moscow Region
  RUSSIAN FEDERATION

File name	File description	Records
IAEA1247_01.001	Information file	101
IAEA1247_01.002	CEM95 Manual in LaTex format	3966
IAEA1247_01.003	Fortran source 1	2007
IAEA1247_01.004	Fortran source 2	675
IAEA1247_01.005	Fortran source 3	2990
IAEA1247_01.006	CEM95 executable for PC (MS Fortran)	0
IAEA1247_01.007	Input Test 1	6
IAEA1247_01.008	Input Test 2	6
IAEA1247_01.009	Input Test 3a	6
IAEA1247_01.010	Input Test 3b	6
IAEA1247_01.011	Author's output of Test 1 (with PC)	213
IAEA1247_01.012	Author's output of Test 2 (with PC)	103
IAEA1247_01.013	Author's output of Test 3 (with PC)	1017
IAEA1247_01.014	Data Bank's output of Test 1 (with VAX)	640
IAEA1247_01.015	Data Bank's output of Test 2 (with VAX)	1855
IAEA1247_01.016	Data Bank's output of Test 3a (with VAX)	1341
IAEA1247_01.017	Data Bank's output of Test 3b (with VAX)	1341
IAEA1247_01.018	Data Bank's output of Test 1 (with PC)	640
IAEA1247_01.019	Data Bank's output of Test 2 (with PC)	1855
IAEA1247_01.020	Data Bank's output of Test 3a (with PC)	1341
IAEA1247_01.021	Data Bank's output of Test 3b (with PC)	1341
IAEA1247_01.022	DOS file-names	21