... The most powerful and widely used methods to calculate the scattering matrix of a fractal cluster are based on the coupled dipoles methods (e.g. the Discrete Dipole Approximation, DDA) and the theory of light scattering by a cluster of spherical particles [2-4]. ... At present the procedure of calculation of the scattering matrix is well developed for both an oriented cluster of spherical particles and for chaotically oriented clusters of such particles [4]. ...

/0004-6361:20011562 c ESO 2002 Astronomy Astrophysics Bispectrum speckle interferometry of the massive protostellar object S140 IRS 1: Evidence for multiple outflows G. Weigelt1 , Y. Y. Balega2 , T. Preibisch1 , D. Schertl1 , and M. D. Smith 1 2 3 3 Max-Planck-Institut fur Radioastronomie, Auf ... Multiple outflows from S140 IRS 1 the arcs in our image, as we have demonstrated by fitting their morphologies with the predicted cavity shapes of the jet-driven outflow model. ...