Accelerated self-consistent radiative transfer based on the Monte- Carlo method. S. Wolf, Th. Henning.

PROGRAM SUMMARY
Title of program: MC3D
Catalogue identifier: ADMH
Ref. in CPC: 132(2000)166
Distribution format: tar gzip file
Operating system: Compaq TruUnix 4.0F, SuSE Linux V4.3 ... V6.3
High speed store required: 50MK words
Number of bits in a word: 8
Number of lines in distributed program, including test data, etc: 61382
Keywords: Astrophysics, Radiative transfer, Interstellar matter, Circumstellar shells.
Programming language used: Fortran
Computer: Alpha Workstation , Intel Pentium/Pentium II.

Nature of problem:
For the interpretation of spectra, images, and polarization maps of young stellar objects (YSO) and active galactic nuclei (AGN), radiative transfer simulations provide the necessary basis. Nowadays, for the interpretation of very high-resolution maps, there exists a strong need for a code which solves the radiative transfer problem even in the case of very complex model configurations (e.g., clumpy dust density distributions, binary systems, direct usage of dust density distributions obtained from hydrodynamical simulations).

Method of solution:
The radiative transfer problem is solved with the help of the Monte-Carlo method. The radiatve energy is partitioned in so-called test photons. Scattering, absorption and re-emission processes by spherical dust grains are considered. Images, polarization maps, and spectral energy distributions (SED) of the considered objects can be obtained.

Restrictions:
The program as presented can handle one dust component defined by a certain radius and chemical composition. However, this is not a principal restriction. It works best for dust density configurations with an optical depth of about tau=10**-3 ... 10**+3.

Typical running time:
The typical running time of the program depends on the complexity of the problem and the geometry of the model. It amounts to several minutes ... several hours.

Unusual features:
None