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Spherical Tori

The spherical torus (ST) machine has recently emerged as an innovative example of fusion confinement that could allow progress to be made in fusion energy development. For example, experiments are conducted with spherical tori to establish the physics principles of the low aspect ratio. Although the ST plasmas are similar to the standard aspect ratio tokamak plasmas in many ways, the range of physics parameters can lead to important new plasma behaviours such as increased stability. In addition, creating plasma in spherical tori reduces transport because of the flow shear and geometric configuration.

Signatories : Japan | United States | European Atomic Energy Community (EURATOM) |
For more information: Under development

Current Projects (Annexes)

Annex I. Co-operation on ST Science R&D


Annex II. Co-operation on the PHysics and Technology of future spherical Torus Devices
The purpose of this Annex is to accelerate progress of research on the physics and technology of future Spherical Torus devices through co-ordination of activities and exchnage of technical information relating to the physics and technoloyg challenges which are common to a range of future Spherical Torus devices.


Annex III. Co-operation on Steady State Operation of Fusion Devices
The purpose of this Annex is to accelerate progress of research on the physics and technology of steady state operation of fusion devices through co-ordinated planning and co-operative research. Close co-operation with other Implementing Agreements is planned, particularly those on Co-ordination of Tokamak Programmes and Co-operation in Development of the Stellerator-Heliotron Concept.