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A Proposed Experiment to Study Relaxation Formation of a Spherical Tokamak with a Plasma Center Column

S. C. Hsu·X. Z. Tang
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Abstract

A spherical tokamak (ST) with a plasma center column (PCC) can be formed via driven magnetic relaxation of a screw pinch plasma. An ST-PCC could in principle eliminate many problems associated with a material center column, a key weakness of the ST reactor concept. This work summarizes the design space for an ST-PCC in terms of flux amplification, aspect ratio, and elongation, based on the zero-beta Taylor-relaxed analysis of Tang & Boozer [Phys. Plasmas 13, 042514 (2006)]. The paper will discuss (1) equilibrium and stability properties of the ST-PCC, (2) issues for an engineering design, and (3) key differences between the proposed ST-PCC and the ongoing Proto-Sphera effort in Italy.

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S. C. Hsu, X. Z. Tang. 2006-05-19. A Proposed Experiment to Study Relaxation Formation of a Spherical Tokamak with a Plasma Center Column. https://arxiv.org/abs/physics/0605174

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