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Дата индексирования: Mon Oct 1 23:30:08 2012
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Поисковые слова: meteor
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].
The latter approach was used by us to obtain the massive of data
for neural network training.
We construct a model primarily directed at interpretation of
the observations of interplanetary dust.
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].
However, the observed dependencies of polarization of light scattered
by cometary and interplanetary dust and, in particular, the orientation
of the plane of polarization with respect to the scattering
plane, allows one to conclude that these dust particles are
to be rather chaotically oriented.
Usually to reduce the number of the input parameters one chose
the cluster constituent spheres to be identical.
For the model of a chaotically oriented cluster of such subparticles,
the direct scattering problem has the following input parameters:
the size parameter of the constituent spheres
(where is the radius of spheres,
the wavelength of incident radiation),
the real and imaginary parts of the complex refractive index ,
the number of particles in the cluster () and
parameters describing the cluster structure,
which can be characterized by two parameters [5]:
the fractal dimension and a prefactor constant .
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2003-04-11