Participant 4 (P4)
                        ==================

Dr. V.A. Babenko     - Stepanov Institute of Physics, Belarus Academy of
                       Science, Minsk, BY

Dr. L.G. Astafieva   - Stepanov Institute of Physics, Belarus Academy of
                       Science, Minsk, BY

Dr. A.A. Kokhanovsky - Stepanov Institute of Physics, Belarus Academy of
                       Science, Minsk, BY

Dr. A.F. Sinyuk      - 35 years old; Stepanov Institute of Physics, Belarus
                       Academy of Science, Minsk, BY

P.K. Petrov          - 26 years old; Stepanov Institute of Physics, Belarus
                       Academy of Science, Minsk, BY

This team includes the scientists from the Stepanov Institute of Physics which
was a leading center of studies of light scattering and its various applications
in the former Soviet Union. Dr. Babenko performed many different researches in
the field of light scattering by spherical and non-spherical particles. Dr.
Astafieva is an expert in thermophysics and optics. Dr. Kokhanovsky is a
well-known specialist in approximate methods of light scattering. Dr. Sinyuk
has solved several inverse tasks in atmosphere optics. The recent works of these
scientists on the subject of the project are as follows:

                   Task 1 (Light scattering theory)

A detailed study of the optical properties of inhomogeneous and anisotropic
spherical particles was done in the book of Prishivalko, Babenko, and Kuz'min
("Scattering and absorption of light by inhomogeneous and anisotropic spherical
particles." Nauka i Tekhnika, Minsk, 1984).

A description of various approximate methods in light scattering by spherical
and non-spherical particles was presented in the book of Kokhanovsky ("Optics
of Light Scattering Media". Wiley, Chichester, 1999).

The variational boundary condition method was developed by Petrov & Babenko
("The variational boundary condition method for solving problems of light
scattering by nonspherical particles." J. Quant. Spectrosc. Rad. Transfer,
v. 63, 237, 1999) to solve the problem of light scattering by non-spherical
particles. An improved algorithm for T-matrix computations of electromagnetic
radiation scattering by spheroidal objects based on the expansions of the Bessel
and Legendre functions in finite series was suggested by Babenko ("Improved
algorithm for T-matrix computation of EM scattering by spheroidal objects." in:
Light scattering by nonspherical particles: theory, measurements, and
application (ed. M.I. Mishchenko, L. Travis and J.W. Hovenier), N.Y., 1998,
p.159).

The size effect in metallic nanoparticles was studied in the paper of Oshchepkov
& Sinyuk ("Optical sizing of ultrafine metallic particles:  retrieval of
particle size distribution from spectral extinction measurements." J. Colloid
Interface Science, v. 208, 137, 1998).

The internal thermal fields in non-rotating spheroidal particles illuminated by
intense laser pulse were considered by Astafieva & Babenko ("Heating of a
spheroidal particle by intense laser radiation." J. Quant. Spectrosc. Rad.
Transfer, v. 63, 459, 1999). It was found that the heating of particles was very
inhomogeneous and the difference in temperatures could reach several hundred
kelvin.

                   Task 3 (Electronic database)

Dr. Babenko has created a database (under FoxPro/DOS) that contains about 8000
references to the papers devoted to the problem of light scattering by small
particles.

There exists a large number of light scattering codes developed by different
persons in the Stepanov Institute of Physics. These codes can treat both single
size particles (such as homogeneous and layered spheres, infinite cylinders,
spheroids, spheres with variable refractive index, etc.) and polydisperse
ensembles.

                   Task 5 (Astrophysical applications)

The inverse problem of determination of refractive index and size/shape
distributions from atmospheric experiments has been solved for non-spherical
particles by Oshchepkov, Isaka, Gayer, Sinyuk et al. ("Microphysical properties
of mixed phase and ice clouds retrieved from in situ airborne measurements."
Geophys. Research Letters, 1999, in press.).

Heating and destruction of particles (including terrestrial aerosol particles)
were considered in a number of papers by Prishivalko, Astafieva, and Leiko
("Heating and destruction of particles exposed to intense laser radiation."
Appl. Opt., v. 35, 965, 1996), Astafieva, Prishivalko, and Leiko ("Disruption
of hollow aluminum particles by intense laser radiation." J. Opt. Soc. Amer.,
v. B14, 432, 1997), Astafieva & Prishivalko ("Heating of solid aerosol
particles exposed to intense optical radiation." Int. J. Heat Mass Transfer,
v. 4, 489, 1998), Prishivalko, Babenko et al. ("On thermal destruction of
atmospheric ice grains by radiation with lambda=10.6 micron." Atmosph. Ocean
Optics, v. 11, 1, 1998), Astafieva & Babenko ("Heating of a spheroidal
particle by intense laser radiation." J. Quant. Spectrosc. Rad. Transfer, v. 63,
459, 1999). The approach developed will be used in consideration of heating and
crystallization of circumstellar dust grains.

P4 team:

4.1. Prishivalko A.P., Babenko V.A., Kuz'min V.N. (1984)
     Scattering and absorption of light by inhomogeneous and anisotropic
     spherical particles.
     Nauka i Tekhnika, Minsk, 264 pp.

4.2. Prishivalko A.P., Astafieva L.G., Leiko S.T. (1996)
     Heating and destruction of particles exposed to intense laser radiation.
     Applied Optics, v. 35, 965-972.

4.3. Astafieva L.G., Prishivalko A.P., Leiko S.T. (1997)
     Disruption of hollow aluminum particles by intense laser radiation.
     Journal of Optical Society of America, v. 14, 432-436.

4.4. Astafieva L.G., Ledneva G.P. (1997)
     Thermal effect of pumping intensity on active medium of neodymium-glass
     microlaser.
     Applied Optics, v. 36, 9360-9370.

4.5. Kokhanovsky A.A., Macke A. (1997)
     Integral light scattering and absorption characteristics of large
     non-spherical particles.
     Applied Optics, v. 36, 8785-8790.

4.6. Oshchepkov S.L., Sinyuk A.F. (1998)
     Optical sizing of ultrafine metallic particles:  retrieval of particle
     size distribution from spectral extinction measurements.
     Journal of Colloidal & Interface Science, v. 208, 137-146.

4.7. Kokhanovsky A.A., Babenko V.A., Barun V.V. (1998)
     On asymptotic values of light fluxes scattered by large spherical
     particles between two angles.
     J. Phys. D: Appl. Phys., v. 31, 1817-1822.

4.8. Kokhanovsky A.A. (1999)
     Optics of Light Scattering Media.
     J. Wiley, Chichester, 217 pp.

4.9. Petrov P.K., Babenko V.A. (1999)
     The variational boundary condition method for solving problems of light
     scattering by nonspherical particles.
     Journal of Quantitative Spectroscopy & Radiative Transfer, v. 63, 237-250.

4.10.Astafieva L.G., Babenko V.A. (1999)
     Heating of a spheroidal particle by intense laser radiation.
     Journal of Quantitative Spectroscopy & Radiative Transfer, v. 63, 459-468.