This issue of Laser and Particle Beams includes papers
presented at the Workshop on “Fast High Density Plasma Blocks Driven
by Picosecond Terawatt Lasers” held at the University of Western
Sydney, Campbelltown Campus, Australia from 1–4 December 2004.
The main motivation for this international workshop was to bring
together scientists and engineers in the fields of inertial fusion
sciences, high-energy-density physics, inertial fusion energy (IFE), and
other related research and applications.
The joint specialists from the USA, China, Poland, Germany, and
Australia was to focus within a comparably small group on a very narrow
defined topic (to distinguish from other meetings, e.g., Schilling, 2003; Desai,
2003; Honrubia & Tikhonchuk, 2004;
Batani & Wooton, 2004; Giulietti, 2004), in order to provide an intensive
exchange of information about very unusual results on intense picosecond
laser-plasma interaction differing drastically from the usual main stream
of observations.
It was a special advantage that the specific results of the main
stream were presented by high caliber experts as E. Mike Campbell (Senior
Vice President of General Atomics, San Diego, CA, USA), Scott Wilks
(Lawrence Livermore National Laboratory, Livermore CA, USA), Dieter H.H.
Hoffmann (Head of the Plasma Division of the GSI and Chair of Nuclear
Physics, Technical University Darmstadt, Germany), and others, showing
their rich information about the general achievements and to exchange the
views with experts involved with the unusual observations. These were
pioneered by the measurements of Jan Badziak (Institute of Plasma Physics
and Laser Microfusion, Warsaw, Poland) in combination with unique
measurements at the Institute of Physics of the Chinese Academy of Science
in Beijing, and the leadership of Jie Zhang who only could send
representatives to explain the work there.
These unusual phenomena were first understood theoretically on the
basis of the many years of work in Australia (Heinrich Hora, University of
New South Wales, Sydney) and associates including the team working
numerically in the group of plasma physics at the University of Western
Sydney, School of Quantitative methods and Mathematical Science. The high
laser intensity interaction process avoids the usually happening
relativistic self-focusing and is understood as a skin layer acceleration
of plasma blocks by the nonlinear (ponderomotive) force. The favor of a
most fruitful cooperation between the Australian group together with
connected teams in Warsaw, Prague, and Beijing, Mianyang and associated
centers led to a clarification of several experimental, numerical, and
theoretical facts about the block generation. It was then most important
that leading experts about the usual relativistic interaction processes
and generation of intense proton beams discussed the details of the
mechanisms and their differences.
It was an opportunity also to receive overviews of large-scale
facilities for this research in the USA, Europe, and China, and about the
latest results on laser fusion energy generation. The different
acceleration processes induced the study of related applications and
general aspects how the processes in double layers and Debye sheaths can
be generalized to metal physics and even to a new model of nuclear forces
and quark-gluon plasmas.
The international workshop provided some excellent outcomes and
results, which can be used for further collaboration in IFE research and
applications. Participative and encouraging discussion sessions were very
fruitful. A series of meetings on the subjects are expected to follow to
help spark Fusion research in Australia and be a support group mechanism
for some large IFE research laboratories around the world.
I would like to thank the workshop co-organizers and all my
specialized colleagues and friends from all the parts of world for making
the time to come to Australia. I would like to thank the University of
Western Sydney and the Australian Institute of Physics in supporting this
workshop. I would also like to thank the friendly catering staff that
provided excellent hospitality for the duration of the workshop.
I would also like to thank Prof. Dieter Hoffmann, the Editor-in-Chief
of the Laser and Particle Beams, for giving us the opportunity to
publish the contributions to the Workshop in this Special Issue. Finally,
we appreciate the contributions of all authors and referees to this
Issue.
