PSR-0137 MARLOWE 15B.

1. NAME OR DESIGNATION OF PROGRAM:  MARLOWE 15b.

3. DESCRIPTION OF PROBLEM OR FUNCTION

The MARLOWE program simulates atomic collisions in crystalline targets using the binary collision approximation. It follows out the consequences of launching an energetic atomic projectile, from either an external beam or an interior site, into a target. The targets may have many material regions, each with its own arbitrary (triclinic) crystal structure and with many kinds of atoms. The program follows the slowing-down of the primary particle and, if desired, that of all target particles which are displaced from their lattice sites, until they either leave the target or fall below a selected low kinetic energy. All cascades may be initiated in undamaged material or damage may be accumulated from one cascade to another; cascades may be run in groups of a selected size. The User's Guide contains a detailed listing of changes in Version 15 and a summary of changes in earlier versions.
  
Version 15b of MARLOWE, dated 5 December 2002, includes some error corrections for the previous release. The new package includes Version 3 of TABULA, a program which uses MARLOWE interatomic potential energy functions to tabulate the classical elastic scattering integrals and related data.
  
News about Marlowe will be posted on the developer's website from time-to-time http://www.ssd.ornl.gov/Programs/Marlowe/Marlowe.htm.

4. METHOD OF SOLUTION

The particle trajectories are constructed as series of binary encounters between the projectiles and the initially stationary target atoms. Elastic scattering is governed by one of several interatomic potentials. The interactions which bind atoms into crystals are modelled by including binding energies between atoms and their original lattice sites as well as binding to the entire crystal. Inelastic (electron excitation) effects are included in a low-energy (< ~25 keV/amu) approximation.
  
Provision is made for users to supply alternative interatomic potential functions, inelastic energy-loss functions, initialization procedures, and analysis procedures. The program is documented in a detailed User's Guide in HTML format, as well as in the scientific literature.

5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM

As distributed, MARLOWE and TABULA are limited to five chemically distinct kinds of atoms. MARLOWE is limited to 32767 displaced atoms in a single cascade. These and most other program limits are readily altered, depending on the problem requirements and the machine size available.

6. TYPICAL RUNNING TIME

MARLOWE running times depend very strongly on the problem studied, but can range from a few minutes to many hours, depending on the initial projectile mass and kinetic energy, whether or not full cascades are generated, the masses of the target atoms, and the number of cascades generated. TABULA running times are very short, typically a few seconds. A set of 21 test problems is supplied and requires less than three minutes on a 166MHz Pentium PC.

- M. T. Robinson:
'MARLOWE Binary Collision Cascade Simulation Program, Version 15b, A Guide for
Users' (December 5, 2002).
- M. T. Robinson:
'Computer Simulation Studies of High-Energy Collision Cascades,' Phys. Rev. B,
67, 396-400 (1992).
- M. T. Robinson:
'The Temporal Development of Collision Cascades in the Binary-Collision
Approximation,' Nucl. Instrum. Methods in Phys. Rev. B48, 408-413 (1990).
- M. T. Robinson:
'Slowing-Down Time of Energetic Atomic in Solids,' Phys. Rev. B, 40, 16,
10717-10726 (1989).

11. MACHINE REQUIREMENTS

The current versions of MARLOWE, TABULA, and MPP can be run on UNIX and UNIX-like systems, including IBM RS/6000 AIX, DEC Alpha Digital Unix, Sun SunOS5, Mac OS X (Darwin) and Pentiums under Linux and Windows systems. They can easily be adapted to other operating systems as long as a suitable Fortran compiler is available.

13. OPERATING SYSTEM UNDER WHICH PROGRAM IS EXECUTED

MARLOWE and TABULA are designed to be highly portable. The programs are written in Fortran 77, fully compatible with the Fortran 90 standard, and have been used for many years on many different computers. The codes run under UNIX , Linux, Windows 95/98/ME/NT/2000/XP, and Mac OS X 10.2 (Darwin 6.0). systems. Some procedures written in C are included in the Unix version. Compilers are required on all computers. No executables are included. The GNU f77 compiler can be used on most systems.
  
Marlowe15B was tested at RSICC on the following systems:
Micron P3 650 mHz running Windows 2000 with GNU77 2;
Dell PowerEdge 2300 running Redhat Linux Version 7.0 with GNU77 2.96;
IBM 44P 270 running AIX 4.3.3 with XLF 7.1;
IBM 43P-260 running AIX 4.3.3 with XLF 6.1;  
SUN UltraSparc 60 running SunOS 5.6 with GNU77 5.23.

15. NAME AND ESTABLISHMENT OF AUTHOR

Contributed by: Radiation Safety Information Computational Center
                Oak Ridge National Laboratory
                Oak Ridge, Tennessee, USA
Developed by:   Oak Ridge National Laboratory
                Oak Ridge, Tennessee, USA

Source codes
Scripts
Test problems
Electronic documentation