CCC-0588 MORSE-EMP.

1. NAME OR DESIGNATION OF PROGRAM:  MORSE-EMP: General Purpose Monte
Carlo Multigroup Neutron and Gamma-Ray Transport Code System with
Array Geometry Capability.

3. DESCRIPTION OF PROGRAM OR FUNCTION

MORSE-CGA was developed to add  the capability of modeling rectangular lattices for nuclear reactor  cores or for multipartitioned structures. It thus enhances the capability of the MORSE code system. The MORSE code is a multipurpose neutron and gamma-ray transport Monte Carlo code. It has been designed as a tool for solving most shielding problems. Through the use of multigroup cross sections, the solution of neutron, gamma-ray, or coupled neutron-gamma-ray problems may be obtained in either the forward or adjoint mode. Time dependence for  both shielding and criticality problems is provided. General three-dimensional geometry may be used with an albedo option available at any material surface. Isotropic or anisotropic scattering up to a P16 expansion of the angular distribution is allowed.

4. METHOD OF SOLUTION

Monte Carlo methods are used to solve the forward and the adjoint transport equations. Quantities of interest  are then obtained by summing the contributions over all collisions,  and frequently over most of phase space.
Standard multigroup cross sections, such as those used in discrete ordinates codes, may be used as input; either CCC-254/ANISN, CCC-42/DTF-IV, or CCC-89/DOT cross section formats are acceptable.
Anisotropic scattering is treated for each group-to-group transfer by utilizing a generalized Gaussian quadrature technique.
The Morse code is organised into functional modules with simplified  interfaces such that new modules may be incorporated with reasonable ease. The modules are (1) random walk, (2) cross section, (3) geometry, (4) analysis, and (5) diagnostic.
The MARS module allows the efficient modeling of complex lattice geometries. Computer memory requirements are minimized because fewer body specifications are needed and nesting and repetition of arrays  is allowed. While the basic MORSE code assumes the analysis module is user-written, a general analysis package, SAMBO is included. SAMBO handles some of the drudgery associated with the analysis of random walks and minimizes the amount of user-written coding. An arbitrary number of detectors, energy-dependent response  functions, energy bins, time bins, and angle bins are allowed. Analysis is divided for each detector as follows: uncollided and total response, fluence versus energy, time-dependent response, fluence versus time and energy, and fluence versus angle and energy. Each of these quantities is listed as output. The diagnostic module provides an easy means of printing out, in useful form, the information in the various labeled commons and any part of blank COMMON. The module is very useful to debug a problem and to gain further  insight into the physics of the random walk.

5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM

Flexible
dimensioning techniques require the use of a large container array in blank COMMON.

6. TYPICAL RUNNING TIME

On a PC 386 running at 25 megahertz under MS  DOC4.01, The following times were noted: problem 1 took about 4 minutes; problem 4 took 11 minutes; problem 5 took 6 minutes; the collision density problem using the MORSECD.EXE for a PC 386 took about 7 minutes; the MORSEXR program took only a few seconds.

The eight test cases included in the package were executed at the NEA-DB on a PC DELL 466/L (processor 80486, 67 MHz). The values of the CPU time displayed in next table are the ones printed out at the end of the execution of each job.

---------------------------------------------------------
| Sample    | Description                     | CPU time |
| Problem # |                                 |(minutes) |
---------------------------------------------------------
|           |                                 |          |
|    1      | Point fission source in air     |   0.37   |
|           |                                 |          |
|    2      | Secondary gamma-ray dose rate   |   2.98   |
|           |                                 |          |
|    3      | Time dependent sec. gamma ray   |   3.62   |
|           | dose rate (adjoint case)        |          |
|           |                                 |          |
|    4      | Fission Problem                 |   1.07   |
|           |                                 |          |
|    5      | Time dependent fission problem  |   0.55   |
|           |                                 |          |
|    6      | Gamma ray dose rate             |   0.86   |
|           |                                 |          |
|    7      | XCHECKR Run                     |  a few   |
|           |                                 | seconds  |
|           |                                 |          |
|    8      | Collision Density problem       |   1.16   |
|           |                                 |          |
---------------------------------------------------------

7. UNUSUAL FEATURES OF THE PROGRAM:

8. RELATED AND AUXILIARY PROGRAMS

This package is a personal computer implementation of CCC-474C/MORSE-CGA, Version 1, originally released by ORNL in 1985. Experimental and Mathematical Physics Consultants converted the codes and support CCC-588/MORSE-EMP.

10. REFERENCES:

- T.M. Jordan:
  Informal Notes (September 18, 1990).
- M.B. Emmett:
  MORSE-CGA, A Monte Carlo Radiation Transport Code with Array
  Geometry Capability
  ORNL-6174 (April 1985).
- M.B. Emmett:
  The MORSE Monte Carlo Radiation Transport Code System
  ORNL-4972 (February 1975), ORNL-4972/R1 (February 1983),
  ORNL 4972/R2 (July 1984).
- J.T. West and M.B. Emmett:
  MARS, A Multiple Array System Using Combinatorial Geometry
  NUREG/CR-0200, Volume 3, Section M9 (December 1984).
   SCALE, A Modular Code System for Licensing Evaluation
   NUREG/CG-0200 (ORNL/NUREG/CSD-2) Revision 2.
- M.B. Emmett:
  PICTURE, A Printer Plot Package for Making 2-D Pictures of MARS
  Geometries
  NUREG/0200, Volume 3, Section M12 (December 1984).
   SCALE, A Modular Code System for Performing Standardized Computer
   Analysis for Licensing Evaluation
   NUREG/CR-0200 (ORNL/NUREG/CSD-2) Revision 2.
- M.B. Emmett, L.M. Petrie and J.T. WEST:
  JUNEBUG-II, A Three-Dimensional Geometry Plotting Code
  NUREG/0200, Volume 2, Section F12 (December 1984).
   SCALE, A Modular Code System for Performing Standardized Computer
   Analysis for Licensing Evaluation
   NUREG/CR-0200 (ORNL/NUREG/CSD-2) Revision 2.
- S.N. Cramer:
  Applications Guide to the MORSE Monte Carlo Code
  ORNL/TM-9355 (August 1985).
- NEA/DB:
  Appendix to the MORSE-EMP Report (January 94).

11. MACHINE REQUIREMENTS

The executable programs which were compiled with Microsoft FORTRAN Version 5.0 using overlays will run on any PC with 640k of memory. The programs compiled with the Lahey F77-EM/32  compiler will run only on a PC 386 with a 80387 math coprocessor and at least 4MB of memory. A graphics monitor is required for the JUNEBUG program.

The eight sample problems were run at the NEA/DB on a
PC DELL 466/L (processor 80486, 67 MHz, base memory of 640 Kbyte and extended memory 7456 Kbyte).
The file-size of the executable versions to run the sample problems  is of the order of 320 Kbyte for all the sample problems, with the exception of the executable to run sample problem # 7 (XCHECKR run)  which size is 135 Kbyte.

13. OPERATING SYSTEM UNDER WHICH PROGRAM IS EXECUTED

The Microsoft FORTRAN Version 5.0 and Microsoft Macro Assembler were used for compilation and linking for the IBM PC version. For the PC 386, the  Lahey F77-EM/32 compiler was used.

MS-DOS 6.0 , programs compiled with the FORTRAN77 Lahey compiler F77L-EM/32 (Version 5.11) and linked with the linker 386LINK.

14. OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS:

15. NAME AND ESTABLISHMENT OF AUTHORS

Experimental and Mathematical Physics Consultants, Gaithersburg,
Maryland.
Oak Ridge National Laboratory, Oak Ridge, Tennessee.

File name	File description	Records
CCC0588_01.001	MORSE.INF Information file	685
CCC0588_01.002	MORSEZ.EXE Self-extracting archive file	0
CCC0588_01.003	DOS file-names	2