Infrared extinction by aggregates of SiC particles: Comparison of different theoretical approaches

نویسندگان

  • Anja C. Andersen
  • Harald Mutschke
  • Thomas Posch
چکیده

Particle shape and aggregation have a strong influence on the spectral profiles of infrared phonon bands of solid dust grains. In this paper, we use a discrete dipole approximation (DDSCAT; [1]), a cluster-of-spheres code following the Gérardy-Ausloos approach (MQAGGR; [2]) and a T-matrix method (SCSMTM; [3]) for calculating IR extinction spectra of aggregates of spherical silicon carbide (SiC) particles. We compare the results obtained with the three different methods and discuss differences in the band profiles.

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تاریخ انتشار 2005