The Amsterdam Light Scattering Database
Hester Volten*, Olga Muñoz#,
Joop Hovenier*, Rens Waters*
*Astronomical Institute “Anton Pannekoek”,
University of Amsterdam, Netherlands
#Instituto de
Astrofísica de Andalucía, CSIC, Granada,
Last update:
September 2008
Table of content
Amsterdam Light Scattering Database Tables
Articles and background information
Aerosol particles
In recent years a considerable amount of experimental single scattering
matrices as functions of the scattering angle have been obtained with the light
scattering facility in Amsterdam, for samples of randomly oriented small mineral
particles in air (aerosol particles) with broad ranges of sizes and shapes.
From these data, it has become clear that particle shape is highly important in
determining the overall light scattering behavior of these samples.
To provide an incentive for the use of our data in further research and applications, we have decided to make our experimental data more easily available by storing our data in digital form in this database. All data have been previously published in scientific journals. The database contains the following data for several samples of mineral aerosol particles in random orientation:
1. Tables of scattering matrix elements
as functions of the scattering angle from at most 3 to 174 degrees at two
wavelengths, 441.6 nm and 632.8 nm.
2. Tables of size distributions as measured with a laser diffraction
method.
3. Scanning Electron Microscope (SEM) images of the particles that are
indicative of their shape characteristics.
4. Information about the origin, color, composition and/or the complex
refractive index of the samples, when available.
Information on the accuracy of the data
is provided, whenever possible.
We intend to update this database regularly with new measured scattering
matrix results.
Hydrosol particles
Scattering data for hydrosol particles are also available in the database: 15 types of phytoplankton and two types of mineral particles. The information for these particles is more limited than for the aerosol particles. The database contains the following data for several samples of hydrosol particles in random orientation:
1. Tables of the scattering function and
the degree of linear polarization for incident unpolarized light, as functions
of the scattering angle from 20 to 160 degrees at a wavelength of 632.8 nm.
2. Information or estimates pertaining to the name, classification,
size, shape, and complex refractive index of the samples, when available.
Organization of the database
In the tables below you find the light
scattering database. In the left column the various samples are listed. They
are linked to a "Fact and Figures" page, where you can find
information about the samples, e.g., about their composition, refractive index,
etc. In addition, figures of scattering matrix elements and size distributions
can be found there. The scattering matrix element data are given in a tabular
form, through links in adjacent columns for measurements using red light (632.8
nm), and, whenever available, for measurements using blue light (441.6 nm).
Also links to Scanning Electron Microscope (SEM) images or Transmission
Electron Microscope (TEM) images and tables of the size distributions are
provided, when available. We note that the laser diffraction size distributions
were obtained without assumptions about the refractive indices of the materials
of the particles.
Click here for:
general information about the composition and refractive index,
general information about the aerosol SEM images,
the definition of the scattering matrix,
an explanation of the normalization of the scattering matrix,
an extensive explanation of the size distributions.
In addition to data for individual samples, we also provide average scattering matrices composed of combined data, and synthetic matrices that cover a complete scattering angle range from 0 to 180 degrees.
Lastly, we would like to remark the
following:
1. When we refer to log r, r refers to radii of projected-surface
equivalent spheres and is always expressed in micrometers.
2. For refractive indices, we use m=n-ik, with n,k larger
or equal to 0 (Van de Hulst, 1957,"Light scattering by small
particles", Wiley, NewYork).
3. Different conventions are used for Stokes parameters and,
consequently, for (the sign of) F34/F11 . We
always use the convention following Van de Hulst, 1957 (see Hovenier and Van
der Mee, Astronomy and Astrophysics, 128, 1-16, 1983, and the book Transfer of
Polarized Light in Planetary Atmospheres, Basic Concepts and Practical Methods,
by J.W. Hovenier, C. van de Mee, and H. Domke, Kluwer Academic Publishers,
Dordrecht, 2004).
4. The values of all aerosol scattering functions F11
have been normalized to 1 at a scattering angle of 30 degrees. The values of
all hydrosol scattering functions F11 have been normalized to
0.00841 (
Amsterdam
Light Scattering Database Tables
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AEROSOL PARTICLES |
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FACTS AND |
SCATTERING |
SCATTERING |
SIZE DISTRIBUTION |
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Average Matrices and Synthetic matrices |
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| Synthetic Scattering matrix of Martian analog particles | synthetic matrix at 632.8 nm | corresponding expansion coefficients |
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Test particles |
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COSMIC DUST ANALOGS – FLUFFY AGGREGATES |
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HYDROSOL PARTICLES |
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Articles and background information
The articles below are posted with permission from their publishers. Single copies of an article can be downloaded and printed only for the reader's personal research and study.
§ The aerosol data in this database have been published in these articles.
§ The hydrosol data in this database have been published in this article.
§ More information about the database can be found in these articles.
§ More information about the experimental setup can be found here.
§ Pictures of the experimental setup, and more.
§ Links to other interesting light scattering websites and databases.
Questions or comments?
We welcome all feedback!
Please e-mail Hester
and Olga.