March 2008 ISSUE 25
Meetings
ASTRONOMICAL POLARIMETRY 2008: Science
from Small to Large Telescopes
6-11 July 2008, Fairmont Le Manoir Richelieu, La Malbaie Québec, Canada
Dear
Colleague,
You are
kindly invited to participate in the conference “Astronomical
Polarimetry 2008” You will
find all the details on our website www.astro.umontreal.ca/astropol2008
The website is now open for registration and abstract
submission. We point out that the first 20 graduate students who register and
who will present a paper (oral or poster) will receive a reduction of their
registration fees. Contributed papers may be presented as oral or poster
papers. However since time is limited, we can not guarantee that your choice
will be met. The science organizing committee will make selections based on the
abstracts received by the abstract deadline. You will be notified in advance if
your contribution has been retained for an oral presentation.
DATES AND DEADLINES
Third Announcement: 1-Apr-2008
Abstract Deadline: 1-May-2008
End of Early Registration: 23-May-2008
Late Registration Deadline: 6-June-2008
Contact email address: pol2008@astro.umontreal.ca
Mie Theory 1908-2008
Present developments and interdisciplinary aspects of light scattering
Universität Halle-Wittenberg
Gustav Mie's original 1908 paper on the color of Gold colloids is
continuously cited. This demonstrates that light scattering by spherical
particles is still a large topic of interest in different scientific
disciplines. These include e.g. astrophysics, optical particle characterization
and computational graphics. With this conference we like to commemorate Gustav Mie and Mie's Theory by bringing
together scientists from different disciplines to discuss the latest
developments in the practical application of light scattering. We especially
like to invite young researchers to present their research in a talk or by a
poster.
The conference will be organized following the 11th Conference on
Electromagnetic and Light Scattering by Nonspherical
Particles, 7-12 Sept. 2008,
Preliminary
list of invited speakers
Anja C. Andersen, Niels Bohr Institute
Rosaria Vetrano, von Karman Institute
Christine Böckmann, Universität Potsdam
Jeppe R. Frisvad, TU Denmark
Alessandro Battaglia, Universität Bonn
Nils Damaschke, Universität Rostock
Adrian Doicu, DLR
Thomas
A. Germer, NIST
Gerard
Gouesbet, Universite de Rouen
Evely Hesse,
Philip
Laven,
Daniel
Mackowski,
Ingrid
Mann,
Paul
A. Martin,
Christian
Mätzler, Universität Bern
Olga
Munoz, I. Astrofisica de Andalucia
Timo A. Nieminen,
Ruhr-Universität Bochum
Rosalba Saija, Università di Messina
Registration: If you are interested to
participate or like to present a talk on a topic related to the scope of the
conference please register on the webpage http://www.physik.uni-halle.de/Mie of
the conference. All necessary information can be found there.
Venue: Martin-Luther-Universität Halle-Wittenberg, Halle, Saxony-Anhalt, Germany,
where Gustav Mie was Professor of Physics from 1917
to 1924, before he joint University of Freiburg.
Deadlines:
Early Registration
till 1st of May 2008, submission of abstracts till 1st of June 2008
Fee: The conference fee will be 60 E
for registration before 1st of May 2008 and 80 E
for later registration.
Organizing committee
Wolfram Hergert, Institut für Physik, Universität
Halle-Wittenberg, Halle, Germany
Thomas Wriedt, Institut für Werkstofftechnik, Bremen,
Germany
Contact
and more information wolfram.hergert@physik.uni-halle.de,
thw@iwt.uni-bremen.de
http://www.physik.uni-halle.de/Mie
New Position
Postdoctoral Position Available for Research in Aerosol Detection,
Naval Research Laboratory,
The
Aerosol Optics Section of the Optical Sciences Division at NRL is seeking a motivated
Postdoctoral candidate for research and development of a novel method in
aerosol detection and analysis. The project is entitled
“Rapid Identification of Biological Aerosols” Within the
project there are a range of activities that span from basic research to
application development:
~Aerosol
Generation and Flow Dynamics
~Electrospray Generation and Application
~Electrodynamic Control of Charged Particles
~Laser
Fluorescence Spectroscopy
~Detector
Characterization and Data Acquisition (e.g. Labview)
~Biomolecular Labeling Techniques (e.g. molecular beacons, antibodies,FRET)
~Bioaerosol Characteristics
Experience
or knowledge of all topic areas is not expected, but the ability to work in a
hands-on laboratory setting, to assist in experimental design, while working
towards an application goal is of primary importance. Applicants that have
experience, and/or enthusiasm to learn to work with electronic and optical test
equipment are desired.
Potential
applicants should be a
Those
interested in more details of the project or to apply should contact either:
Dr. Matt Hart
202-767-0122
Matthew.Hart@nrl.navy.mil
or
Dr. Jay Eversole
202-767-9523
jay.eversole@nrl.navy.mil
Information
about the Naval Research Laboratory can be found at: www.nrl.navy.mil
New Papers
M. A. Yurkin K. A. Semyanov, V. P. Maltsev, and A. G. Hoekstra, "Discrimination of
granulocyte subtypes from light scattering: theoretical analysis using a granulated
sphere model," Optics Express 15, 16561-16580 (2007).
http://www.opticsexpress.org/abstract.cfm?id=148215
Abstract: We perform extensive simulations of light scattering by a granulated
sphere in the size and refractive index range of human granulated leucocytes
using the discrete dipole approximation. We calculate total and depolarized
side scattering signals as a function of the size and refractive indices of
cell and granules, and the granule volume fraction. Using typical parameters
derived from the literature data on granulocyte morphology, we show that
differences between experimentally measured signals of two granulocyte subtypes
can be explained solely by the difference in their granule sizes. Moreover, the
calculated depolarization ratio quantitatively agrees with experimental
results. We also use the Rayleigh-Debye-Gans
approximation and its second order extension to derive analytical expressions
for side scattering signals. These expressions qualitatively describe the
scaling of signals with varying model parameters obtained by rigorous
simulations, and even lead to quantitative agreement in some cases. Finally, we
show and discuss the dependence of extinction efficiency and asymmetry
parameter on size and volume fraction of granules.
M. A. Yurkin, A. G. Hoekstra, R. S. Brock, and J. Q. Lu,
"Systematic comparison of the discrete dipole approximation and the finite
difference time domainmethod for large dielectric scatterers," Optics Express 15, 17902-17911 (2007).
http://www.opticsexpress.org/abstract.cfm?id=148490
Abstract: We compare the discrete dipole approximation (DDA) and the finite
difference time domain (FDTD) method for simulating light scattering of spheres
in a range of size parameters x up to 80 and refractive indices m up to 2.
Using parallel implementations of both methods, we require them to reach a
certain accuracy goal for scattering quantities and then compare their
performance. We show that relative performance sharply depends on m. The DDA is
faster for smaller m, while the FDTD for larger values of m. The break-even
point lies at m = 1.4. We also compare the performance of both methods for a
few particular biological cells, resulting in the same conclusions as for
optically soft spheres.
ADDA update
The
new version of ADDA code (0.78) has been released. This release incorporates a
number of new features, significant speed improvements, and several minor
bug-fixes. The list of changes, together with the new package and executable
for Windows, can be found at the ADDA web site: http://www.science.uva.nl/research/scs/Software/adda/
All ADDA
users are advised to upgrade to a new version. Potential users are invited to
take a look and try this code.