Radiative transfer problem in dusty galaxies: ray-tracing approach

A new code for evaluation of light absorption and scattering by interstellar dust grains is presented. The radiative transfer problem is solved using ray-tracing algorithm in a self-consistent and highly efficient way. The code demonstrates performance and accuracy similar or better than that of previously published results, achieved using Monte-Carlo methods, with accuracy better than ~ 3% for most cases. The intended application of the code is spectrophotometric modelling of disk galaxies, however, it can be easily adapted to other cases that require a detailed spatial evaluation of scattering, such as circumstellar disks and shells containing both point and distributed light sources.