NASA Laboratory Astrophysics Workshop -- Registration

[Friedrich Huisken <p2hufr@uni-jena.de>]

Dear Organizer,
attached please find my registration and abstract.
If possible, I will be glad to give an oral contribution, otherwise
a poster.
The check about the conference fee will be sent to Cara Loomis.
Sincerely yours
Friedrich Huisken

-- 
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Professor Dr. Friedrich Huisken
Laboratory Astrophysics and Cluster Physics Group
Institute for Solid State Physics
Friedrich-Schiller-Universität Jena
Helmholtzweg 3, D-07743 Jena
Phone: +49-3641-9-47354
Fax: +49-3641-9-47308
e-mail: friedrich.huisken@uni-jena.de
http://www.physik.uni-jena.de/~exphys/astrolab/
------------------------------------------------------


%
% Sample abstract for submission to NASA LAW 2006.
% See page 181-183 of Leslie Lamport's LaTeX book (second edition)
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\documentclass{article}

\begin{document}

\title{Spectroscopic Studies of PAHs in Supersonic Jets and Liquid Helium Droplets}

\author{Friedrich Huisken, Angela Staicu, Serge Krasnokutski,\\and Thomas Henning }

\date{04 January 2006}

\maketitle

\begin{abstract}
Neutral and cationic polycyclic aromatic hydrocarbons (PAHs) are discussed as possible carriers of the
diffuse interstellar bands (DIBs), still unassigned astrophysical absorption features observed in the spectra
of reddened stars. Despite the importance of this class of molecules for astrophysics and nanophysics (PAHs
can be regarded as nanoscale fragments of a sheet of graphite), the spectroscopic characterization of PAHs
under well-defined conditions (low temperature and collision-free environment) has remained a challenge.
Recently we have set up a cavity ring-down spectrometer combined with a pulsed supersonic jet expansion to
study neutral and cationic PAHs under astrophysical conditions. PAHs studied so far include the neutral
molecules anthracene and pyrene as well as the cationic species naphthalene$^+$ and anthracene$^+$. Employing
another molecular beam apparatus, the same molecules (except of the cationic species) were also studied in
ultracold liquid helium droplets. This novel technique combines several advantages of conventional matrix
spectroscopy with those of gas phase spectroscopy. Notable advantages are the possibilities to study
molecules with rather low vapor pressure, to achieve equilibrium between vibrational, rotational, and
translational degrees of freedom, and to use a mass spectrometer facilitating spectral assignments. The most
recent studies were devoted to phenanthrene and the more complicated (2,3)-benzofluorene. These molecules
were investigated in the gas phase by cavity ring-down spectroscopy and in liquid helium droplets using
depletion spectroscopy. For benzofluorene, the present studies constitute the first measurements carried out
in the gas phase and in helium droplets. In contrast to previously studied PAHs, the shift induced by the
helium droplets was very small (blue shift between 4.5 and 4.9 cm$^{-1}$ for all vibronic bands). In addition
to commercially available molecules, we have also studied PAHs which were produced by CO$_2$ laser pyrolysis
of benzene/ethylene gas mixtures. Up to now, no coincidence between experimental and interstellar band
positions was found.
\end{abstract}





\end{document}

Registration form
-----------------------------------------------------------------------------------------------------
Last name: Huisken
First name: Friedrich
Middle name/initial: -
Affiliation: Institute of Solid State Physics
             (Joint Laboratory Astrophysics Group of the Max Planck Institute of Astronomy) 
Street Address: Helmholtzweg 3
City: Jena
State: 
Postal Code: D-07743
Country: Germany
Tel: +49-3641-947354
Fax: +49-3641-947308
E mail: friedrich.huisken@uni-jena.de
Citizenship*: Germany
Abstract title: Spectrsocopic Studies of PAHs in Supersonic Jets and Liquid Helium Droplets
Special requirements:
*Non-US citizens should contact Cara Loomis if travel reimbursement for the Workshop is required.