NEA-0809 PREANG.

1. NAME OR DESIGNATION OF PROGRAM:  PREANG. A statistical-model code to calculate nuclear cross sections, particle-emission spectra and angular distributions for projectiles with energies above 10 MeV.

3. DESCRIPTION OF PROBLEM OR FUNCTION

The code calculates cross sections, particle emission spectra and their angular distributions  for reactions of type A(x,y)B, where x and y can be n, p, alpha, He-3, d or t. The nuclear model is based upon the time-integrated master-integrated master-equation approach of the excitation model.  The calculated cross sections contain precompound and compound contributions. The angular distributions are calculated according to the model of G. Mantzouranis, D. Agassi and H.A. Weidenmueller (1).

4. METHOD OF SOLUTION

The mathematical solution of the generalized master equations is given in (2). A rather complete description of the method is given in (3).

5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM

The validity of the  model is restricted to projectile energies of 10 to 50 MeV. Only first-particle emission cross sections are calculated. The level densities are assumed to be described by continuum distributions; no spin and parity dependences are accounted for.

6. TYPICAL RUNNING TIME

The sample problem takes 0.37 CP seconds on a CYBER-175.
NEA-DB executed the test case on CDC CYBER 174 in 2.4 seconds.

7. UNUSUAL FEATURES OF THE PROGRAM:

8. RELATED AND AUXILIARY PROGRAMS

The code is a modified version of PREEQ by E. Betak, Comp. Phys. Comm. 9, 92 (1975) and 10, 70 (1975).

10. REFERENCES

- G. Mantzouranis, D. Agassi and H.A. Weidenmueller:
  Phys. Lett. 57B, 220 (1975).
- J.M. Akkermans:
  Phys. Lett. 82B, 20 (1979).
- J.M. Akkermans, H. Gruppelaar, G. Reffo:
  Phys. Rev. C22, 73 (1980).

- J. M. Akkermans and H. Gruppelaar:
  Calculation of Preequilibrium Angular Distributions with the
  Exciton Model Code PREANG
  ECN-60  (May, 1979).
  Note: The outcome of the sample problem in this reference is
        slightly different from that of the present code version.
- H. Gruppelaar and P. Nagel:
  "International Nuclear Model and Code Comparison on
   Pre-Equilibrium Effects"
  NEANDC-204"U"/INDC(NEA)6 (September 1985).

11. MACHINE REQUIREMENTS:  Main storage 46,675 octal words on CYBER 174.

13. OPERATING SYSTEM UNDER WHICH PROGRAM IS EXECUTED:  NOS-BE.

14. OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS:

15. NAME AND ESTABLISHMENT OF AUTHOR

          J.M. Akkermans and H. Gruppelaar
          Netherlands Energy Research Foundation
          ECN, Petten, P.O. Box 1
          1755 ZG PETTEN
          Netherlands

File name	File description	Records
NEA0809_01.002	PREANG INFORMATION	30
NEA0809_01.003	SOURCE (FORTRAN-4)	1616
NEA0809_01.004	JCL	17
NEA0809_01.005	SAMPLE CASE INPUT	36
NEA0809_01.006	SAMPLE CASE OUTPUT	365