Abstract Details

Combining the "Kinetic Tandem" and the "Kinetic Stabilizer" Concepts

Author: Richard F. Post
Submitted: 2006-01-03 17:10:18

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Abstract Text:
Combining the “Kinetic Tandem� and the “Kinetic Stabilizer� Concepts

R. F. Post
Lawrence Livermore National Laboratory

The “Kinetic Stabilizer Tandem Mirror� (K-S T-M){1,2,3] relies on a novel means of stabilizing an axially symmetric mirror machine proposed by Ryutov [4] and demonstrated in the Gas Dynamic Trap [5] at Novosibirsk. In the K-S T-M stabilization against the MHD instability of an axisymmetric mirror is effected by using axially directed ion beams to create an “anchor� plasma on the expanding field lines outside the mirrors. The forerunner “Kinetic Tandem� (K-T) [6] concept involved a similar use of ion beams to create density peaks at the end of a long solenoidal field with no mirrors at its ends. In the K-T, by building a high-density peaked ion distribution in situ, a confining potential is generated that both confines and stabilizes the plasma, but at the expense of needing a very long central confinement chamber to create a positive power balance against the power required to maintain the beams. This paper describes how one might combine the two concepts to produce a K-S T-M whose stabilizing plasma is held confined between the extreme ends of the system and the outer mirror by an outer secondary “plugging� potential created by the K-T technique. One possible advantage of using the “dual� technique to create a K-S T-M is that it could prove advantageous in suppressing possible “trapped particle� modes that could arise in the region between the stabilizer plasma and the T-M plugs. This is because the new stabilizer plasma would more closely represent the one occurring in the GDT, where no evidence of trapped-ion modes was seen, owing to the effluent nature of the stabilizing plasma that was produced in that device. Preliminary calculations of the application of the K-T to the K-S T-M will be described.

Work performed under the auspices of the U S Department of Energy by the University of California Lawrence Livermore National Laboratory under contract No. W-7405-ENG-48

[1} R. F. Post, Trans. of Fusion Technology, 39, 25 (2001)

[2] R. F. Post, Trans of Fusion Technology, 43, 195 (2003)

[3] R. F. Post, T. K. Fowler, R. Bulmer, J. Byers, D. Hua, L. Tung, Trans of Fusion Technology, 47, 49 (2005)

[4] D. D. Ryutov, “Axisymmetric MHD-Stable Mirrors,� Proc. of Course and Workshop, Varenna, Italy, Vol II, 791 (1987)

[5] P. A. Bagrynsky, et. al., Trans. of Fusion Technology, 35, 79 (1999)

[6] R. F. Post, Trans of Fusion Technology, 35, 40 (1999)


Characterization: A5

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