Applied Plasma Physics and Fusion Energy
Academic Year 2006-2007
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Wednesday, October 18, 2006
3:45 PM
479 EBU-II
“X
(-pinch) marks the spot for fusion”
In today’s society it is important to develop a clean
and inexpensive form of energy that will not deplete the earth’s limited
resources. Consequently, we turn to fusion. This seminar will include a
brief orientation on fusion and the proposed methods to achieve ignition
through inertial confinement.
The integration of plasma physics research to inertial
confinement fusion (ICF) will be discussed, followed by a look at the ongoing
x-pinch work at UCSD. Here x-pinches are a mechanism designed specifically
to study high energy density physics (HEDP) while eliminating some of the
stringent requirements of ICF.
X-rays from 1-10keV have been recorded
coinciding with 2-5 micron sources. >From these signals the emission
spectra from various wire materials and configurations have been calculated and
will be presented. Images of laser probing that show the evolution of the
x-pinch plasma will be displayed in conjunction with a brief description of the
physics involved. In addition, recent experiments that have explored the
plasma jets emerging from the cross point of the wires will be mentioned.
Parameters affecting the propagation (velocity and aspect ratio), as well as
the development of m=0 and m=1 instabilities, will be touched upon.
To conclude, future work, (specifically wire arrays), will be discussed.
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Wednesday, October 11, 2006
3:45 PM
479 EBU-II
David Jimenez Rey
Laboratorio Nacional de Fusión por Confinamiento Magnético CIEMAT
Madrid, Spain
“Ionoluminescence and its application to fusion plasmas”
Luminescent materials have useful characteristics for diagnostic and control systems in fusion devices. This seminar will discuss the application of such radiation-hard luminescent materials in a diagnostic probe for measuring fast ion losses close to the edge of hot plasmas in the TJ-II stellarator. In future operations, the plasma will receive up to 2 MW of additional heating from two neutral beam injector (NBI) systems in which neutral hydrogen is accelerated to 35 keV, and from which theoretical studies predict that losses due to fast ions could reach 30% of the injected power. Ionoluminescent screens exhibit good response linearity and good relative sensitivity to charged particles accelerated to keV and MeV energies. Furthermore, the immunity of such phosphors to electromagnetic interference and ground loops, as well as their compactness (only a thin screen is required), makes them well suited for use as broadband radiation detectors in the harsh environments encountered in fusion devices. One of their main attractions is their ability to tolerate high integrated particle fluxes. These screens must exhibit low and brief delayed luminescence (or “afterglow”). Materials that can be used as a fast ion diagnostic for fusion are still debated. For example, in ITER there exists concern over energetic (>MeV) ion-induced damage. In this presentation, the theory and design of luminescent detectors will be described, data acquired in TJ-II will be presented, and possible applications in other devices such as ASDEX, JET, and ITER will be discussed.
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Wednesday, October 4, 2006
3:00 AM
479 EBU-II
Martin Tolley and Christopher Spindloe
Target Fabrication Laboratory, Central Laser Facility
CCLRC Rutherford Appleton Laboratory,
“Microtarget
fabrication at the Rutherford Appleton Laboratory”
Capabilities in fabrication of microtargets for use in high power laser experiments are presented with special focus on emerging technologies such as MEMS techniques. Characterization techniques are also discussed. New and novel target types are shown, particularly low density (metal) coatings and in-progress work on wire array targets. Paradigms for delivery of solid targets to high repetition rate lasers are discussed.