My friend, Bill Ghiorso, has generously allowed me to use some storage within this server in order to share some of my work with friends and colleagues. I started to work in the field of computational plasma physics 5 years ago, motivated by experimental problems in H^– production at the Los Alamos Neutron Science Center (LANSCE). My friend Kevin Bowers has been and continues to be my mentor and guide in this field. Check out this news: Following-up on his Best Paper Award at the Supercomputing '06 Conference, he is a Gordon Bell finalist for the coming SC '08 for his work on the Cell Processor-based Roadrunner Supercomputer at LANL.

In the links below you will find some material on the ion source technology whose understanding is sought, including diagrams, photos and animations.

Summary of what you will find in the links:

1. An invited presentation delivered at the last ICNSP conference which gives some context to the animations included below (see i).
2. An animation of a simulated filament discharge in hydrogen. Here, electrons (cyan) are emitted from filament surfaces (red). Through a series of reactions, these electrons produce H⁺, H₂⁺, and H₃⁺ positive ion species (blue). Positive ions impinging on the leftmost surface produce negative hydrogen ions which then travel through the plasma and exit the ion source. This simulation is able to provide input for an actual re-design.
3. The “configuration space” animation is accompanied by a “longitudinal phase space” animation (iii), which mostly provides a “sanity check.” It shows the time evolution of the particles’ longitudinal speeds, showing the areas of acceleration and drift. Note the increase of the velocity spread with distance and plasma density. Under some conditions, streaming instabilities appear in the beam. Watch out! The files are really big movies in .avi format. Please hover over the links to see the size of the files. If you have problems with playback while the movies are shown on the browser window, I suggest to do a save link as and play it from your hard drive. [Publication of this material has been authorized as documented by assigned Los Alamos Unlimied Release (LA-UR) classification numbers.]

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