User Guide for the Discrete Dipole Approximation Code DDSCAT (Version 5a10)

Abstract

DDSCAT.5a is a freely available software package which applies the "discrete dipole approximation" (DDA) to calculate scattering and absorption of electromagnetic waves by targets with arbitrary geometries and complex refractive index. The DDA approximates the target by an array of polarizable points. DDSCAT.5a requires that these polarizable points be located on a cubic lattice. DDSCAT.5a10 allows accurate calculations of electromagnetic scattering from targets with "size parameters" 2 pi a/lambda < 15 provided the refractive index m is not large compared to unity (|m-1| < 1). The DDSCAT package is written in Fortran and is highly portable. The program supports calculations for a variety of target geometries (e.g., ellipsoids, regular tetrahedra, rectangular solids, finite cylinders, hexagonal prisms, etc.). Target materials may be both inhomogeneous and anisotropic. It is straightforward for the user to import arbitrary target geometries into the code, and relatively straightforward to add new target generation capability to the package. DDSCAT automatically calculates total cross sections for absorption and scattering and selected elements of the Mueller scattering intensity matrix for specified orientation of the target relative to the incident wave, and for specified scattering directions. This User Guide explains how to use DDSCAT.5a10 to carry out EM scattering calculations. CPU and memory requirements are described.

Added more information for non-Unix sites, and new target option PRISM3 (triangular prism). 42 pages, 5 figures

References in corpus (1)

• Improvements of the Discrete Dipole Approximation method

Cited by in corpus (13)

• The discrete dipole approximation: an overview and recent developments
• The discrete dipole approximation for simulation of light scattering by particles much larger than the wavelength
• Effective medium theories for irregular fluffy structures: aggregation of small particles
• Discrete-dipole approximation with polarizabilities that account for both finite wavelength and target geometry
• Radiative torques alignment in the presence of pinwheel torques
• Convergence of the discrete dipole approximation. II. An extrapolation technique to increase the accuracy
• Infrared extinction by homogeneous particle aggregates of SiC, FeO and SiO2: comparison of different theoretical approaches
• The 'nanobig rods' class of gold nanorods: optimized dimensions for improved in vivo therapeutic and imaging efficacy
• Criteria for mixing rules application for inhomogeneous astrophysical grains
• Composite Circumstellar Dust Grains
• Cosmic dust optical properties: Numerical simulations and future laboratory measurements in microgravity
• Real Dust Particles and Unimportance of the Poynting-Robertson Effect
• Interstellar extinction by fractal polycrystalline graphite clusters?